Yes, that is bud rot. I hope that not all of your plants are affected you are able salvage something from this grow.
I was going to cut the 6 or 8 bud tips off and let the plant keep going for 7 or 8 more days as it will be no rain and in the 70-80s.
Is that a mistake? Should I harvest the plant?
If you have been able to remove all of the rot, you can give it a go, but watch very closely. If this were my only plant, I might consider an early harvest to insure that I had something to show for my efforts. Rot can take hold very quickly, as you have now learned. Tough lesson.
Rot and pests are the main reason that I only grow indoors, I just don’t want to deal with those things. The added expense of growing indoors is worth it to me.
I thankyou for the advice!