You will probably find that you will use a lot of different methods for holding the strips to the forms as you go along. I use hot glue but try to minimize how often. Hot gule makes it difficult to remove the strips from the forms. Most frequently I use rubber bands to hold the strips to the frames. The picture below depicts a hull during construction.

I drive two 1 5/8" square drive deck screws into each side of a form about 3" from the edge. I like the square drives because the head is smaller than typical dry wall screws. I have a big bag of 3" diameter office supply rubber bands and some 7" or 8" diameter rubber bands. Ioften double up on the bands to get the right amount of force. I then only use hot glue where the strip comes away from the hull after the bands are removed.

In between forms I will clamp the strips into alignment with these small spring clamps (link below). They are small and light weight, so they do not put a sag in the strips between forms and the polyurethane glue does not stick to the plastic cauls, like it does with the PVC cushions on metal spring clamps.

http://www.amazon.com/gp/product/B00BRL59UM?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

As to your original question of how long does the glue need before you can unclamp it. It depends on the glue. I use polyurethane glue (Gorilla is one brand). I use it for several reasons.
1.) it is easy to test with your finger, as to when it is ready to unclamp. PVA's skin over and can be soft in the middle after the surface seems solid, hence the edges will creep.
2.) Epoxy bonds well to polyurethane unlike the PVA's such as Tightbond. Hence, I never get the cloudy white/yellow areas between strips of which some some builders complain.
3.) It is better at gap-filling than the PVA's.
4.) It foams and cross-links and as a result it is easier to sand.
5.) Polyurethane glue has a longer open time, yet if the humidity is high enough and the temperature is high enough, it cures faster. To answer your original question: I average about three hours between strips.

Disadvantages of Polyurethanes
a.) it is more expensive.
b.) it gels to an unusable state in an opened bottle in a couple months.
c.) it turns your finger tips black, which takes a weeks worth of hand washing to remove. This can be almost eliminated if you keep some abrasive, waterless, hand cleaner (Go-Jo is a brand) in the shop and clean your fingers with it as soon as you are done with the glue.