I do have some good news, as I have changed phone it seems that the EE coverage has suddenly got better (even though no new masts are here) even though on every other phone I have ever used it has been slow and unusable or on a good day 4Mbps down and 2UP on Three being the worse and EE except O2 and Vodafone. Now it seems to be 40Down 20Up at a push hanging around 20-30 Down 3-10UP so it seems the iPhone 12s have got a decent Arial well at least against my previous windows phones and iPhone 6/ 7 Plus. I did this test in the room I like to call the nuclear bunker because the walls are 40CM think and any signal is hard, to call previously I had to wire in a wireless Access point and drill it onto the wall.
Tomorrow I am going to run some tests in another building which has always had bad coverage on every provider for anything as its basically a Tin Can only to be made worse by having a lift in the middle so hopefully I will get more than my record of 47Mbps on the roof and 10 inside. If its the case that I get coverage I won't be as bothered for the change to Vodafone even if there is a mast 30M away the EE and Three one is 100-200M away and I am in the middle between 3 Masts so its a bit patchy whereas Vodafone has full coverage with more masts than you could imagine.
I will let you know how the tests go but considering the speed increase sitting at home its promising A bit strange too.