judging week 5-7 progression and what you feed, i'd lean lockout. Some claw in leaves, but late in flower, so it is tough to figure out what the cause is with multiple options. Looks tohave a bitof a claw going on, so more likely high on nutes than low.
But, looks like K or Mg deficiency symptoms? Rule out K-deficiency by checking guaranteed labels and calculate ppm you give. if it is okay, and you regularly give cal-mg, it's very unlikely either of these since 'enough' is provided... you may have too much Ca if you mix with hard water... these are all guesses and you need to cross-reference your recent behaviour and facts you have access to that i do not... don't blindly listen to me or anyone else on this stuff unless they have all the necessary info, which is impossible most times.
As long as it doesn't permeate the canopy, should be fine. as long as it doesn't progress too quickly, should be fine.
another thing to ensure is proper before doing anything is your pH. Based on diary, you should be fine there.