Bookworm,
I believe that you are also supposed to notify the point at which you are going to cross the FIR boundry, not just the time.
I do as per your post for the time, and just make sure that I have a FIR crossing point as one of the points somewhere in the route section (not specifically maked any differently).
Admittedly, they don't seem to care, and I'm not sure how many people bother.
As for the GAR, it should be sent to NCU & Immigration. They don't share the form between the agencies.
dp