You can't really slow the process much.

When the plant begins to produce seeds, the trich. production stops. The trichs won't grow anymore, and if it is pollinated at 4 weeks flowering, that is about how potent it's going to be. Trichcome production stops once seeds start growing.

Too bad man, that's a bummer. Hermi's happen by stress. Commonly by light leaks, so check your grow area to make sure there are no light leaks, and for next time, don't put your plant rhough any kind of stress, and if you do, make sure it is light stress.

And never, ever, ever! Look at your plants while the light is OFF. People like to do this and it will hermi your plant. When the light is off, it must be off for those 12hrs with no light leaks.

Peace.