It apparently took Parallels support over a month to work out that there was actually a bug in this module… it appears they even charged the people for support who brought the bug to their attention:
Link: BUG: Acronis module – another atismodbackupmng process is running
Scheduled jobs came back with:
> Error: another atismodbackupmng process is running!
> TrueImage backup task #2
Apply the hack to their Plesk code fixed the issue… until next Plesk upgrade no doubt.