Am pretty close to bringing in to the LBS
Given the trouble you are having shifting the existing bb, please do not take it to the same lbs. They have clearly not greased or properly prepared the threads.
I'll give the shop a 2nd chance.
Back to my initial comment few pages back, I suspect it's a UN300 which I've seen fail prematurely.
@coventry_eagle started
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Given the trouble you are having shifting the existing bb, please do not take it to the same lbs. They have clearly not greased or properly prepared the threads.