If you stack images, Siril reports different values for EXPTIME and LIVETIME. The EXPTIME seems to be the length of the sub. The LIVETIME is the total exposure time.

AAVSO is pulling the EXPTIME and using it as if it were the total time. I really don’t know who is right here. I’ve found sites that (somewhat ambiguously) support both interpretations.

I’m just wondering if someone can authoritatively say Siril is correct. If so, I guess I would have to get AAVSO to change (which will be difficult).

For example, ASTAP writes this

So they seem to be using EXPTIME as the total time, not the sub times

Before we were using EXPTIME as the total exposure time, but in fact many software are using LIVETIME instead.

So we have updated.