This may not be a flashy or creative task but it comes up in quite often in every form of production. This practical video covers the way to set a custom start frame for your composites.
Normally the default is frame 1 but there are quite a few cases, including sequence publishing or shot collaboration with Shotgun, which would require a custom start frame.
We'll run through the preferences and options of how the start frame works in Batch as well as BatchFX.