Huge jump in centiles in only 4 weeks? AC/HC

[Allosaur]

Has anyone had any experience with their baby jumping centiles? At 28 weeks, she was measuring 7th for AC and 90th for HC gulp and now at 32 weeks, her AC is now at the 73rd centile - so a HUGE jump in only four weeks and her HC is now down to 42nd. Is this normal? Nurse doesn't think I have GD but I'm still a bit confused.

In a slightly longer timeframe my little one jumped from 50th for everything at 20 weeks to 95th for head and abdomen at 28 weeks. I wasn’t ever tested for GD as I didn’t fall within a risk group but they did give me fortnightly growth scans as they were worried he’d be huge (I am short and so is husband).
Last scan was at 38 weeks and they induced me at 40+2, but he was born 8lb 3oz on the 75th centile. Those scans can definitely be inaccurate, I had heard so many stories saying a similar thing

My DD jumped from 50th to 90th percentile for AC in 2 weeks (I think HC was 50th to 75th or 80th). Turns out I did have GD. She had another little jump for AC to 95th percentile and then followed that line. Was told to prepare for a baby over 9lb - she was 8lb 6oz.
My consultant actually said herself how wildly inaccurate growth scans are!