I've had the new iPhone 12 for two months now. Previously had the iPhone 8. Can I say how much I hate the swipe from the bottom? I miss my home button. I know I've been told I'll get used to it, but how long will it take? 

I’ve done the same thing with my old iPhone 5s.I still have my old(er) 7Plus as a spare and have my 8Plus set up as new as its tentatively sold. When working with either of them it was a lesson in 'muscle memory' as after 2 days with my 12, I was clumsy and 'drew a blank' several times on the older design when I tried to swipe up and either got nothing, or the control centre
I’ve done the same thing with my old iPhone 5s.