If you are able to get on chat or the phone with an agent, they have been able to do it (I acknowledge that is harder with the app pushing us to the AI chatbot)... I've had service scheduled in Shelton twice by chatting / talking to the agent - it's SO much better than Boston.....
Same - I recently had the wheel hub tightening service done at Shelton and had to call for scheduling as nothing was showing online but they got me in very quickly over the phone. I mentioned in another post that when I was waiting for my truck there were at least 4 Amazon drivers waiting for their Rivian delivery vans to be repaired so my guess is that could have something to do with the scheduling as they try to manage that commercial fleet service as well. Love the Shelton location though and the team there was great.
It may be just a capacity issue? I was there a couple of weeks ago for the knuckle fastener safety check. Chatting to the advisors, they said they were booked solid and currently trying to hire more techs. Good luck, it's a great location and the staff there are excellent.