I've just booked a week on Formentera for the first week of October (£760 room + flight!) so I hope all restrictions have gone by then, otherwise - even though the rules appear to suggest your booster is valid more than the 270 days I'm still not absolutely convinced I won't need a booster nearer the time. Really waiting to see what happens in the late summer when visitors (from the UK) who haven't had that second booster get on.
But frankly unless there's a serious variant I expect all protocols to be lifted by then, in fact I'd be surprised if they weren't gone by the start of the schooliehols.
That aside, masks STILL have to be worn on buses....and here's a thing, Ryanair - at the gate outbound and inbound - insisted on pax wearing masks. Wouldn't allow you on without. Guess what...the cabin crew didn't wear any so most pax took them off for the whole flight. Absolutely not joined-up thinking there.