Try reducing your light schedule to 11 on / 13 off. If you do your research, DJ short and I know Snowhigh (from email) both use 11/13, even for indicas. I have permanently switched to 11/13 for everything, even with indicas, since my last run and everything was fine.
11/13 will prevent late stage re-flowering. Many old timers and breeders use this light schedule.
Snowhigh even recommended to me to use 10.5 / 13.5 and he said that's the sweet spot for ALL plants!
DJ Short said that night time is when the plant put on weigh (i.e. resin, leaves growth, etc). I have not done comparative test myself, but all of the flowers from the 11/13 run with 3 different strains were all caked and resinous.