The EU checking all goods entering the single market is a concequence of Brexit and happened on day 1. I guess I was thinking "if EE now have to charge people, why didn't it happen on day 1?"
I didn't know if they don't actually have to charge people but are going to because they now can.
I wasn't really questioning whether it was Brexit related (it clearly is) but I wondered why it hadn't happened immediately, and whether it was a decision by EE or simply an automatic consequence of leaving the EU (like customs checks).
Companies have been very wary of making changes that are seen as 'negative' changes that could be seen as anti-brexit. There's been a lot of very silly attitudes around the whole thing.
With regards to the impacts of Brexit there are many different types. Some that forced immediate changes, some things that are now allowed that weren't before and some things that were allowed before but no longer are.
Ae you note, the customs changes were (largely) immediate effects that happened over night. There are actually quite a number of customs changes that are being implemented over time, so even there the changes didn't all come into force as the clock struck 11pm UK time.
As for things that are now allowed that weren't before, UK mobile phone companies being allowed to charge for roaming within the EU (and presumably EU mobile cos charging fees for roaming in the UK) became allowable as soon as Brexit happened, but the impact was that it allowed companies to make the choice. It was a removal of a restriction rather than a change that mandated them to charge roaming fees. Indeed, mobile companies could charge nothing at all for any of their services if they wanted.
As for things that changes to things that were allowed before but no longer are: freedom of movement to work and live within the EU and vice versa is an obvious one that comes to mind. I wasn't living or working in the EU at the time of Brexit, but because it happened my options for living or working in the EU are significantly curtailed. That impact has yet to be felt and may simply manifest itself as me not moving to somewhere in the rest of the EU in the future when in an alternative timeline, I may well have done.
A lot of the debate around Brexit has been so moribundly stupid. At least now it is done, there is a bit of space to point out how there are immediate and longer term impacts.