Old Fuji Super G+ 100
My only experience with outdated color film is with Fuji Super G+ 100. It expired in 1998, and I bought a 100 foot roll from Freestyle about 3 years ago, as an out of date, cold stored special. What surprised me about this film, is that it seemed actually faster than the box rated speed. OK, I use sunny 16, and my exposures probably aren't very accurate.
I compared the Super G+ 100 with fresh Fuji Super HQ 100 from Walmart, which I usually use on vacations. Exposing the Super G+ about the same as the Super HQ under similar conditions, I got high contrast and chalky, blocked up highlights. The problem was even worse when I went to the mountains and was shooting at 8000 ft plus elevations. I probably didn't compensate enough for the much harsher light up there. When I shoot some of the Super G+ again, I'll probably rate it at 200.
The other thing I noticed about the Super G+ was it had developed a distinctly warm color balance, and was grainier than the Super HQ, but I guess that should be no surprise.
This is different film than what you're using, and my experience may not apply here, but it might be useful to the general knowledge base.
BTW, Freestyle is still selling the Super G+ 100. They've now dropped the price to $9.99 for a 100 ft roll. I don't think I should recommend it to anyone, but it might be interesting to experiment with.