Brain has deleted all animation knowledge

I’ve come back to an old project, which was my very first attempt at animation and have completly forgot how to amend / update start keyframes after repositioning a camera.
Sorry for long description below for which is probably a simple solution.

I have a camera connected to an empty in my scene.
The empty rotates and the camera follows the rotation.
The Camera also pans in and out as it rotates.
In the center of the scene is a collection of objects that are also animated ( my blend file is to big to upload)
So the camera rotates around the collection " seeing " various moving elements.
The easiest way to descibe this is imagine a camera rotating around a house, starting at the rear of the house, it rotates around to the front of the house.
As the camera approaches the front of the house it “sees” the front door opening and closing in shot, then continues rotating back to the rear of the house.

So in my animation, by the time the camera rotates around to the front the door is already closing and the camera has not seen the opening of the door because of it’s rotation starting point.
I need to reposition the camera so it sees the door opening and closing, that I understand, but if I manually move the camera starting point, how do I update the starting keyframe for this position and where do I reset it in UI.
I happy witrh the speed of the rotation, so I don’t want to increase the speed to see the door opening and closing.

Any Help would be great
Cheers
A