mold/bud rot

I lost 3 tents to bud rot recently. I scrubbed every surface and used fungicide more than once before starting again with 2 GG4 autoflowers. The yongest is now 8-9 weeks old in a 10 gal fabric pot with 70/30 coco perlite and it looks healthy. I noticed recently that the buds had changed color...

Been growing couple years now (random good bagseed) and I average around 2 1/2 oz a plant...with my most recent grow I decided to purchase seeds from reputable banks and now I feel like I've crossed a new threshold...I was used to 2 oz plants but now I'm staring at what might very well be a 2 oz...