Oddly enough, the creamy-coloured stripe on his back turned pinkish today! (I actually tried wiping off the pinkness because I thought it was a stain from rat blood- go figure.) The closer I look at his light-coloured parts (sides, belly, etc.) the more I see pinkish colouration as well. So I think he'll shed soon.

Good to know it's not unusual for them to go so long without shedding! I'll keep that in mind for the future. I thought it was a sign of worse things, but I guess it just shows that each snake is different.