I've had a look at my notes from the meeting, so here's some more info that may or may not be useful.
If they propose closing your branch, they'll give details of one or two alternatives. There will provide, on request, "branch access reports" for these alternatives. They'll say how far they are, what the terrain is, what the parking is like etc etc.
The first thing to do is make sure that the information on these reports is correct - ie, check that the bus company isn'y planning to withdraw a service etc etc.
These alternative branches have to support "minimum access critera" (I think the government decides the criteria, but I can't quite read my notes at that point!)
and ideally be less than a mile from the branch that's proposed for closure.
The reasons that they might decide not to close a branch are:
If the branch they want to close is in an area of high deprivation, and residents don't have access to cars. Especially vulnerable residents - single parents and disabled people ideally. Not elderly people, as they get free bus transport. (At least, they do in Scotland. Presume it's UK-wide)
If the alternative branches don't have the capacity to absorb the additional customers - ie, if they only have one "window" and already have a reputation for huge queues.
If the nearest branch is too far away, if the public transport links are poor and unreliable and if there are parking restrictions.
Lastly, if the alternative branches provide a poorer service - shorter opening hours, no disabled access etc.
They also count the responses they get, so it's probably better to send 100 individual letters that a petition with 100 names.
Remember that they have a set number of POs that they must close, so if a miracle does happen and they keep yours open, they will close another one within the geographic consultation area.
It's a box ticking exercise. I know of only one occasion where the consultation ended in a change of decision. Good luck anyway.