Certainly won't have helped! 1.5cm is a lot - I'm surprised you didn't notice that.
Although any extended physical effort that's over and above what your body's used to can lead to cramp - particularly in the warm conditions we had on Sunday. I think it was warmer than it felt because of the wind, if that makes sense - i.e we were sweating more than we realised. (Tommy's jersey was covered in salt stains!)
I probably did, but due to other issues, upper right arm being the main one, I didn't pick up on it.
Your knees would of known about 1.5cm drop- eek
My knees have been ok
Depends really. 15mm sounds like a lot but only if we assume your saddle was in the perfect position to start with.
What was the specific problem TB?
Cramp intermittently in the inside of the thighs, both low toward the knee and high toward the hip. Calves and hamstrings were ok until the hill that I stopped on.
I started to cramp about 70-75 miles in, fighting the headwinds and managed the problem until I stopped. I had plenty of water but no isotonic.
Edit to add
I did get Isotonic at the last pit stop but by then I think it was too late.
I can't say for certain what caused my cramping issue. I think it was a combination of all the things joined, poor hydration, higher than I'd ridden in temp, headwinds and slight bike fit change.
Lessons learned.
Drink, more than you think you should, but not too much (very hard balance). Eat. Go slower at the start.