Transferring to a new phone network, 2022 edition

Some posts are written so there’s an audience. Some are written to be informative, or amusing. And some are literally just documentation for me which nobody else will care about. This is one of those.

I’ve moved phone network. I’ve been with Three for years, but they came up with an extremely annoying new tactic, and so they must be punished. You see, I had an account with 4GB of data usage per month for about £15pm, and occasionally I’d go over that; a couple of times a year at most. That’s OK: I don’t mind buying some sort of “data booster” thing to give me an extra gig for the last few days before the next bill; seems reasonable.

But Three changed things. Now, you see, you can’t buy a booster to give yourself a bit of data until the end of the month. No, you have to buy a booster which gives you extra data every month, and then three days later when you’re in the new month, cancel it. There’s no way to just get the data for now.1

This is aggressively customer-hostile. There’s literally no reason to do this other than to screw people who forget to cancel it. Sure, have an option to buy a “permanent top-up”, no arguments with that. But there should also be an option to buy a temporary top-up, just once! There used to be!

I was vaguely annoyed with Three for general reasons anyway — they got rid of free EU roaming, they are unhelpful when you ask questions, etc — and so I was vaguely considering moving away regardless. But this was the straw that broke the camel’s back.2 So… time to look around.

I asked the Mastodon gang for suggestions, and I got lots, which is useful. Thank you for that, all.

The main three I got were Smarty, iD, and Giffgaff. Smarty are Three themselves in a posh frock, so that’s no good; the whole point of bailing is to leave Three. Giffgaff are great, and I’ve been hearing about their greatness for years, not least from popey, but they don’t do WiFi Calling, so they’re a no-no.3 And iD mobile looked pretty good. (All these new “MVNO” types of thing seem quite a lot cheaper than “traditional” phone operators. Don’t know why. Hooray, though.)

So off I went to iD, and signed up for a 30-day rolling SIM-only deal4. £7 per month. 12GB of data. I mean, crikey, that’s quite a lot better than before.

I need to keep my phone number, though, so I had to transfer it between networks. To do this, you need a “PAC” code from your old network, and you supply it to the new one. All my experience of dealing with phone operators is from the Old Days, and back then you had to grovel to get a PAC and your current phone network would do their best to talk you out of it. Fortunately, the iron hand of government regulation has put a stop to these sorts of shenanigans now (the UK has a good tech regulator, the Competition and Markets Authority5) and you can get a PAC, no questions asked, by sending an SMS with content “PAC” to 65075. Hooray. So, iD mobile sent me a new SIM in the post, and I got the PAC from Three, and then I told iD about the PAC (on the website: no person required), and they said (on the website), ok, we’ll do the switch in a couple of working days.

However, the SIM has some temporary number on it. Today, my Three account stopped working (indicating that Three had received and handled their end of the deal by turning off my account), and so I dutifully popped out the Three SIM from my phone6 and put in the new one.

But! Alas! My phone thought that it had the temporary number!

I think this is because Three process their (departing) end, there’s an interregnum, and then iD process their (arriving) end, and I was in the interregnum. I do not know what would have happened if someone rang my actual phone number during this period. Hopefully nobody did. I waited a few hours — the data connection worked fine on my phone, but it had the wrong number — and then I turned the phone off and left it off for ten minutes or so. Then… I turned it back on, and… pow! My proper number is mine again! Hooray!

That ought to have been the end of it. However, I have an Apple phone. So, in Settings > Phone > My Number, it was still reading the temporary number. Similarly, in Settings > Messages > iMessage > Send and Receive, it was also still reading the temporary number.

How inconvenient.

Some combination of the following fixed that. I’m not sure exactly what is required to fix it: I did all this, some more than once, in some random order, and now it seems OK: powering the phone off and on again; disabling iMessage and re-enabling it; disabling iMessage, waiting a few minutes, and then re-enabling it; disabling iMessage, powering off the phone, powering it back on again, and re-enabling it; editing the phone number in My Number (which didn’t seem to have any actual effect); doing a full network reset (Settings > General > Transfer or Reset Device > Reset > Reset Network Settings). Hopefully that’ll help you too.

Finally, there was voicemail. Some years ago, I set up an account with Sipgate, where I get a phone number and voicemail. The thing I like about this is that when I get voicemail on that number, it emails me an mp3 of the voicemail. This is wholly brilliant, and phone companies don’t do it; I’m not interested in ringing some number and then pressing buttons to navigate the horrible menu, and “visual voicemail” never took off and never became an open standard thing anyway. So my sipgate thing is brilliant. But… how do I tell my phone to forward calls to my sipgate number if I don’t answer? I did this once, about 10 years ago, and I couldn’t remember how. A judicious bit of web searching later, and I have the answer.

One uses a few Secret Network Codes to do this. It’s called “call diversion” or “call forwarding”, and you do it by typing a magic number into your phone dialler, as though you were ringing it as a number. So, let’s say your sipgate number is 0121 496 0000. Open up the phone dialler, and dial *61*01214960000# and press dial. That magic code, *61, sets your number to divert if you don’t answer it. Do it again with *62 to also divert calls when your phone is switched off. You can also do it again with *67 to divert calls when your phone is engaged, but I don’t do that; I want those to come through where the phone can let me switch calls.

And that’s how I moved phone networks. Stuart, ten years from now when you read this again, now you know how to do it. You’re welcome.

  1. Well, there is: you can spend twenty actual pounds to get unlimited data until the end of the month. But that’s loads of money.
  2. is there an actual camel whose back was broken in some fable somewhere? this is a terribly unfortunate metaphor!
  3. Coverage in my flat — for any network — is rubbish. So wifi calling is a hard requirement. I don’t know why this is — I’m in the city! Maybe the walls all have copper wiring in them like the room that Elodin was imprisoned in, I don’t know
  4. I always buy my own phones, so I only ever need a SIM, and I don’t like being locked in
  5. we, meaning Open Web Advocacy, have worked extensively with the CMA (and other regulators around the world) about assisting and requiring mobile phone manufacturers to provide browser diversity — that is, to make it so you can use web apps on your phone that are as capable as platform-specific apps, and the CMA are great
  6. removing a SIM tray is harder than it looks when you don’t wear earrings. I had to search everywhere to find one of those little SIM tools
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