Sounds like the shop you took it to is flat on their arse. I have a 2006 Yamaha F250 and my lower unit went out. Bill Marine in Portsmouth had me up and running in a week, a brand new lower unit paid for 100% by Yamaha warranty. I'd find it hard to believe that Yamaha has been sitting on your warranty claim since June, a more believable explanation is the shop you took it to didn't take care of you and sat on it this long.
But glad you will be back up soon.
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