I stopped off there a couple of weeks ago, returning to the UK.
There was a Notam regarding PPR and booking. I phoned from Bordeaux and flew direct. Landing fee was about £19 (RV-4) and 100LL available at £1.09/litre.
No problems at all, they were very helpful.
Longer stay parking may be an issue, but it’s probably worth giving them a call to find out.
Popham’s a great airfield, but if you want to go to Southampton……