1) how long, on average, does it take for the pollen sacks to mature? (Indica dominant plant)
2) what are the best conditions under which to store pollen?
3) how long is it viable?
If they are already getting fat they could start popping in a week or so. The sacs usually go lighter and even yellow just before they blow their load.
Clean every speck of plant bits out. I have a 180 micron screen I run it thru and it's real clean. I put the open vial in a jar that has colour changing drying crystals,
Drierite, in it to draw all the moisture out for a few days then seal the vial. You could just heat up some rice in the microwave to drive off the moisture then put that in a sealed jar in place of the crystals. Storing in the freezer should make it last longer but I just keep it in a jar in the safe.
Lasts a good 6 months but I rarely try using it that long. Usually needed it for a project and don't need it again.
1/4 of that vial above could make thousands of seeds so you don't need ounces of it.