OK, I had a HW3 install scheduled, but 3 days later no HW3. Here's the quick version:
I scheduled my car for Service and to have the spoiler finally fitted (got the car in Oct 2018) and was told my FSD computer was available for my car. The service date was Tues Jan 28th at around 8am.
I was told by phone the prior day that my car might not be available for pickup the same day, because higher priority cars might come in on that day (tow-ins) and mine would end up in a queue. I only use my car at the weekends usually anyway, so fair enough.
At 3pm on Weds 29th, I got a call saying the tech had started working on my car, and it was a model that requires "an extra part for the FSD Computer" which is apparently needed to prevent issues with coolant. That part wasn't available, so they suggested I just get the service and schedule the upgrade another time. OK I guess I have no choice.
I picked the car up on Thursday 30th, with no upgrade and no spoiler (I suspect they didn't actually have a spoiler for me, otherwise they'd have done it) but my service was complete costing $614 (Wipers, brake fluid check, brake lubrication, alignment, "cleaner Kool It" (whatever that is) and new dead front pins (free, known issue), new HVAC combination filter. Car is 16 months old with 22k miles.
So... no cigar but $600 poorer. I'll leave it two weeks before asking about this part.