I had a similar situation, with flights booked MXP to LHR then LHR to SFO the following day, on separate tickets. I was thinking of booking the Sofitel since the arriving flight and departing flight both use T5, but I don’t know if that is the correct solution to the “port of entry” rule, or how much we would have to isolate ourselves in the hotel, if at all.

But before asking about it here,I decided to just call BA and amend the booking to put it all on one ticket with a 2-hour layover and airside transit. It took 5 calls before I could stay connected and get into the queue, and after 40 minutes I gave up and yielded my spot in the queue to someone who needs more immediate help (our flight is not until March, so I can wait to do this, and in the meantime the requirements are likely to change).



But I am curious to see what the answer is, so I hope someone responds.