There is a small leaf curled and yellow in your bud (last picture) pull it, it might be infested with budrot.
Yes, I'm seeing it everywhere but better save than sorry.
@goarilla, thank you for your concern! But it's not infected, I've checked it out. I spend 2 hours on the spot inspecting each bud every time I go there. This leaf is yellow and curled because of lack of nutrients (I started flushing more than 2 weeks ago). Usually I remove every yellow leaves but not if it still has a bit of green in it (shows photosynthesis still works).