There’s about a week when they start dumping a little, and then about a week to two weeks after that where they just keep ramping up.
I usually pollinate females starting the second week, and then if pistils continue to develop a week later, a second time. Often i collect pollen and store it in a gasketed dry box for the week. A good dry box can keep pollen viable at least 6 months.
I just used pollen that i collected last September, and it still works, though i notice it seems to have degraded a little.