Yep, basically, getting the new phone on Friday, the new watch on Monday/Tuesday... so I'll probably be fine for paring the existing apple watch plan to the new phone via migration, but I'll have to phone EE to sort out the e-sim for the series 5 ...![]()
I have my fingers and toes crossed for you on Monday, then!
If you do experience any disconnection - they do say it can take up to 24 hours for the behind the scenes stuff to re-align - make sure you press them to credit your account back. You should get a month or two's free Apple Watch line rental out of them!