High disk usage after updating to Kernel 6.11

After updating to Kernel version 6.11 from 6.10 (Nixos-Unstable), I'm seeing a lot of Reading and Writing going on in my Gnome System monitor (in the TBs for each). Is this expected?

I have 2 nvme drives (1TB and 256GB) caching 2 SSDs (8TB and 1TB). I also notice that bch-rebalance is busy doing some cpu work in the 'Processes' tab. Other than that I don't really know what and how to dig any deeper.

If it's not expected but the investigation would be either time-consuming, involved or both, I'm okay with just reformatting and restoring from backups.

Just wanted to ask if it'll eventually stop (if it's expected behavior) before I nuke and pave.

Thanks!