I've been able, using Harry Fox, go get a go ahead in very short 
order. You need to communicate your time line to them and they 
will be able to tell you if you can make the deadline. They will
 also be able to tell you if they can rush the process. This 
usually costs extra. After all they do this every day. It’s their 
only business. For one project we didn't get the final bill until 
about 3 months after the video was complete but the client was
 aware that they may be facing additional charges when the final 
usage was determined. I was able to get a 'probably won't exceed' 
figure from Harry fox and we proceeded from there. If there's 
going to be a problem with a current hit - HFA will usually know 
about it and let you know. That's why it's important to use Pro's 
when dealing with these sticky issues. Also, it's a good idea to 
have a lawyer that is experienced in these matters look over your 
contract so that you will not be held liable for the decisions. 
I do this by listing my Client's as executive producers on all 
projects and making them contractually liable for all talent fees, 
re-use fees and releases. This makes sense on a work for hire basis 
because you loose all control over what is done with the video 
when you turn over the master for duplication.

One more hint. . . never pay for printing, duplication or shipping 
directly. I can’t tell you how many clients I have had in 31 years 
that ordered more dubs than they needed and then took 6 months 
to a year to pay for them.