How to Make the PSTN Switch with Minimal Downtime

Imagine starting the workday like any other, only to realise that your phones aren't working and you've lost your business phone numbers. While January 2027 has been looming at the back of your mind, you might have figured you still have time to upgrade your on-premises Private Branch Exchange (PBX) systems.

But what if I told you that the switch has already started, and exchanges are being shut down as we speak? Well, they are, and if your business is still using an on-prem PBX with your old PSTN lines, it's time to make the switch. As a solutions specialist with 15 years of experience in helping businesses like yours maintain uninterrupted communication, you can trust me when I say that dealing with this early is key.

The PSTN switch-off deadline means the switch is expected to be completed across the UK by January 2027. So, you may have less time to prepare than you think. In this article, we'll unpack the key considerations and strategic steps involved in transitioning an on-premises PBX system away from the PSTN with little to no disruption.

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What This Blog Covers:

• Understanding the Potential Pitfalls
• The Importance of Thorough Planning and Preparation
• Don't Forget Your Analogue Devices
• Minimising Downtime During the Switch
• Don't Wait Until 2027!
• Choosing the Right Partner

Understanding the Potential Pitfalls

As you begin to think about making the switch as smoothly as possible, a good place to start is understanding what could go wrong and why. The biggest challenge I've seen SMBs deal with isn't usually the tech itself, but the admin side. More specifically, it's crucial to ensure that your phone numbers are ported correctly and that your new cloud system is configured to the right standards before installation.

If you're looking to avoid disruptions, then being proactive is key. Many providers are all about the quick sell – 'Sign here today, we'll be in next week'. But rushing leads to mistakes, and mistakes lead to downtime. This is why you should get the switch sorted sooner rather than later – so that you can rest assured that your new system is configured and pre-installed to the right standards.

The Importance of Thorough Planning and Preparation

This is why we at Babble believe in a thorough process defined by planning and testing. Before we even think about installation, we first get a crystal-clear picture of your current system. Like any partnership, we want to know as much about you – or in this case, your comms and connectivity setup – as possible (be prepared for a lot of questions).

At a glance, this is what our initial planning phase looks like:

• Proper Information Gathering: Once you're on board, you'll have a dedicated team that gets to know your existing system inside and out before even thinking about installation. They'll ask about everything – your existing ring groups, data, and how you've got things set up now.
• Pre-Configuration is Key: Given that the top priority is to keep your comms running smoothly, we build and pre-program your whole new cloud system behind the scenes before we even set foot on your site to do the physical install. (Nobody wants any surprises on the day.)
• Understanding Your Current Setup: Our data-gathering journey is a process. We're going to ask about your cabling, your connectivity and pretty much anything comms-related. Avoiding downtime is just the first goal, a close second is ensuring that the transition works for your organisation. For example, if you're thinking about having cordless phones in a warehouse, we'll even check your Wi-Fi coverage to make sure it's up to scratch.
• Site Surveys When We Need To: Look, SMB owners are experts in their field – cars, mortgages, you name it. But telephony? Not so much (that's where I come in). So, if we think you might not know the answers to some of our questions, or if things sound a bit complex, we'll do a site survey before the installation. We'll check your infrastructure and connectivity, and even run test calls. All of this helps us spot potential problems early.
• Identifying Analogue Dependencies: As we assess your system, we critically identify any analogue lines connected to your PBX or PSTN, such as those used for alarms, fax machines (remember those?), and even lifts. This brings me to my next point.

Don't Forget Your Analogue Devices

It's easy to forget that phones aren't our only means of communication and that the PSTN switch-off extends beyond landlines. This means it's not just your PBX you need to think about, but every single device that is still plugged into your current system.

Here are some frequently overlooked devices that you need to make sure are "switch-ready":

• Alarms: You cannot afford to have an alarm system that doesn't work. Speak to your alarm company and find out their plan for the analogue switch-off. Don't just assume it'll keep working.
• Fax Machines: While they're the last of a dying breed, fewer and fewer businesses use fax machines. But if you still rely on fax, we offer a fax-to-email solution. We can port your fax number, and any incoming faxes to land in your inbox as emails.
• Lifts: I don't know about you, but getting stuck in a lift is my worst nightmare. And guess what, lifts often have analogue lines for emergency calls. So, get in touch with your lift operator ASAP to see what their plans are for the switch.
• Loud Bells & Door Entry Systems: Many businesses, especially in warehouse environments, have loud bells connected so they know the phone's ringing over the noise. We've got integration solutions, like Cisco ATA, for these to connect them to the new cloud system. Same with door entry systems: we often use an ATA (Analogue Telephone Adapter) for this kind of thing.
• Video Door Entry: It's worth noting here that cloud solutions in general don't directly support video door entry systems that integrate with your mobile devices. So, if you've got a system where you see who's at the door on your phone screen, that won't work with our cloud setup. You'd likely need to look at integrating your video door entry with your computer system instead.

Minimising Downtime During the Switch

Now that we've spoken about the preliminary work that needs to be taken care of before the switch, let's discuss what comes after. Remember, our main goal is to make this whole switch as smooth and painless as possible. In fact, we don't even want you to notice it happening.

The key to minimal downtime lies in a well-executed transition process, which includes several redundancy measures – here are the main ones:

• Parallel Installation: We often install the new cloud system right alongside your existing PBX. They can both be there simultaneously while we test the new system.
• Temporary Numbers First: Part of the testing phase is initially setting up your new cloud system with temporary numbers. These are essentially placeholders, as we wouldn't want to bother your customers.
• Clever Number Diversion: Then, we divert your main existing phone number to these temporary numbers. So, to the outside world, nothing changes. Your customers still call your usual number.
• The Seamless Fallback: If, for any reason, you hit a snag after the new system is installed, we can simply revert to your old, still-working system. No panic, no major disruption, and most importantly, no disgruntled customers.

Don't Wait Until 2027!

From what we've covered, I'm sure you can see that a proper, smooth transition takes time. So, at this point, you might wonder how much time this takes (which is a great question!). Our implementation phase, from when you sign up to when it's all installed, is usually four weeks at the least. That's what we need to do all that important pre-configuration.

This bears repeating: while January 2027 is the big date everyone talks about, exchanges are being switched off right now, sometimes with as little as 8 to 12 weeks' notice! (Salisbury got switched off way back in 2023). Many local businesses thought it was just a sales tactic, but quickly found out that this wasn't the case.  A scary thought, I know. But it doesn't have to be if you start preparing for the switch way ahead of schedule.

Choosing the Right Partner

This is why you need a provider who understands that the PSTN switch-off isn't just about plugging in some new phones. It's about careful planning, testing and strategising a smooth handover. This takes the weight and the complexity off your shoulders.

I've mentioned how we pride ourselves on our thorough planning and pre-configuration, and have a slightly longer transition period. This isn't about dragging our feet; it's about making sure we get it right the first time and that you see the benefits you're expecting.

Preparing for the PSTN Switch: Act Now for a Smooth Transition

The long and short of it is that switching from your old PSTN lines doesn't have to lead to downtime or lost numbers. If you take the time to plan and prepare, you can achieve a hassle-free transition.

In reality, the PSTN switch-off is happening right now, and the January 2027 deadline is when the entire country is expected to be officially switched over. 

It may seem like a daunting feat, but this is where Babble comes in: we've been helping thousands of businesses like yours navigate this transition. To us, it's not just about plugging in new phones and going on our merry way. We believe that a smooth handover is about careful planning, testing, and strategising.

A proper, smooth transition takes time. Our implementation phase alone requires a minimum of four weeks for crucial pre-configuration. To avoid disruption and ensure your business is "switch-ready", the time to start preparing is now.