Thanks for the heads up mate, I'll see if I can find out why the shaft should need changing....I'm guessing others have done it (whoever told you about it)?! Is the shorter shaft just a fit and forget thing, trying to think what other impacts it would have running a shorter drive shaft!!
How often have you been changing the oil, been told it needs changing pretty regular with the plated diff?!
I first heard about the shaft issue when I posted on here about juddering I was getting around corners. If you read through all the posts around the one you quoted of mine you'll see it mate
The Phase 1 shaft is a fit and forget thing though yes. I have a 172 gearbox in mine. So it could just be that a 182 with the wider track doesn't work with a 172 diff'd box.... Who knows. But basically the Ph1 shaft is 10mm shorter and that was enough to stop my 182 shafts from bottoming out in the diff.
I only put the diff in last spring, and the oil was fresh last summer so I'll probably change it end of this year.