Resize to 1023 rounds up to 1024

Hi everyone,
I have a deliverable of 1023x542. However, when I resize to 1023 it jumps up to 1024. I’ve heard of this issue before, the number not being divisible by 4, but can anyone explain what’s actually happening and why?

I have been looking into the problem with 8-bit files
Export resolutions in 8-bit

But in some cases Flame just seems to round up. Not sure if this is due to 8-bit limits or just trying to prevent bad numbers later on.