WELL, now what a series of fortunate events that was!
TL;DR: Managed to get a 2017 tbMBP 2.8/16/256 upgrade from my 2012 rMBP 2.6/16/256 for FREE, and after they shut down the programme.
I had been aware of this thread but was away when i found out about it, and by the time I'd gotten home, the top case stock had already been "replenished". I went in nonetheless, and was offered a free top case replacement. The genius I dealt with was also kind enough to throw in a display repair, and I was told the whole operation shouldn't take longer than a week (late July/early August). I went in to pick up my seemingly brand new macbook pro about a week later, and posted on here about my semi-success story.
After a few days, I noticed that the computer didn't lie flat on surfaces, ie. it had a wobble. I took it back in to have it looked at and another genius confirmed that indeed it seemed to have a very slight bend (I was told different things by different geniuses at different times, that it was either the display or the top case that were bent, or even both...). At this point they also gave me a free iPhone case, which was an unnecessarily kind gesture, but one they felt inclined to offer for the faulty part. They repeated the same repair, replacing the top case and the display again. When I went to pick it up, however, I immediately noticed that they had replaced the top case with a UK keyboard, whereas I originally had a US keyboard. So the computer was put back into repair, and an order for the correct top case was placed, and I was quoted that it would arrive the following Tuesday, 3 days later.
By Friday, the part hadn't arrived, so I decided to phone in to get an update. I'm not sure what exactly I was told the problem was, but I was advised that the part would arrive the following Tuesday. Around this time, I also became aware of the renewed supply shortages alluded to in the post above this.
I rang Apple the following Tuesday, and was told that the new top case still hadn't arrived. Whether that was due to these stock shortages or to the fact that Monday was a bank holiday here in the UK, I was now presented with two options: (a) let apple keep my computer, and walk home with a new replacement unit which would *have* to have a UK keyboard, or (b) wait for the part and see if they could sweeten the deal in some other way, though there'd be no guarantee as to when that would be. Needless to say, I opted for a new replacement unit, and I couldn't be happier. I consider myself very lucky, as it was clearly a series of unlikely events that lead to this outcome.
I've got to thank the OP, Psynott, once again for drawing attention to this opportunity, and to the friend of mine who pointed me to this thread.
