Certainly fine for a back to back. Most of the time all BA flights use the air bridge (gate 21). The exception is the late night arrival which becomes the early morning departure. This is a bus, which drops you off at the airbridge area. Very unlikely to use the remote passport control which is mainly there for the Iran flights.

The time between flights is not rushed, and in normal ops there is no reason for BA to store aircraft here. What lands departs.

The only one to watch, is depending on loads, BA will sometimes cancel the 19.20 from LHR and keep the 16.45 overnight without the late departure from GOT. This is typically done with at least 2 weeks warning. It is highly unlikely they would cancel either of the two morning flights as these are used for connections. These tend to be prioritised.

KF