Want to save pollen, not easy to collect

This reversed Male and my females in the same tent are on their 6-7 week of bloom. The "male" is starting to senesce. I have been plucking pods and they have pollen. I'm having a difficult time collecting pollen without biomass included. Like dried up anthers and bits of the pods. I'll note that the plant does not produce a huge amount of pollen it seems.

At this point, I'm considering cutting a few tips and drying them to collect. Is this advisable? How long can pollen dry until it needs to be put in the freezer? I'm hoping to store some for my next run... At least 2-3 months.