Pedals were removed, threads were cleaned and re-greased before today’s ride. I checked all chainring bolts. A couple of them I was able to snug up about 1/8 turn (or less). All the chainring bolts on the 30 tooth chainring were all tight. When in the 30 tooth ring standing to climb it is moderately creaky. I rode 69 miles today and the sound persists.

i have not removed the bottom bracket yet, but plan to this afternoon to check the bearings, remove regrease or replace if needed. I’m tempted to purchase a Hope or Phil Wood outboard bearing Shimano 24mm bottom bracket as an upgrade if it is apparent that the 6600 bottom bracket is toast.