yeah you can stop spraying now. Sonlme strains form weak pollen sacks if you touch them they fall off before opening up. But you should be OK. Let me know how things go over the next six weeksThanks @bobqp that explains a lot & provides the reassurance I was after. I'll just continue with the plan.
I've stopped spraying now that the sacks are forming (or should I keep going until they're fully open?).