Fill ACF fields with data from text file

Hey,

I need someone to point me in the right direction. I have some vague ideas about how to approach this but a shove will get me much closer.

I have an ACF form defined that authors have been filling in manually for each post. It gets displayed to readers as a sort of status update at the time the post was written.

The software that is managing that status can output a text file with all of the data I need in it. So, instead of filling in the fields manually, I’d like to [push a button] or somehow get WordPress to go to that file, look for the correct variable names and then copy the values it finds into the form.

This only needs to happen either a) on demand before publication or b) once upon initial publication (not save as draft).