If, like me, you jumped on a eSim when the latest iPhones launched in 2018 and you’re on the iPhone upgrade program, you might want to find out how you actually move that eSim to a new phone come September. I asked the EE Twitter account and it sounds like there’s possibly not a plan in place to do it as yet. It sounds like you may need to do the transfer before you hand the phone back, so just be careful and plan ahead.
** UPDATE **
As you were, it seems it’s much easier then I feared. Thanks Greg!