What you may get from AH Gib is something along the lines of what the Service Standard is - Client Service Charter

In reality, they do normally move considerably quicker on family visas, even for defacto visas which usually have to be supported more and certainly so for a married person.
Certainly I would get on to the police and health checks ASAP as that could delay the processing though they do say for overseas applications you should wait until asked by a Case Officer, though in your case, getting it underway is hardly going to hurt, ie.
. if application is in
. by time you get contacted by a CO, you'can have made arrangements for the health and police checks or even have them.