Ok, thinking outloud here ... cause I don''t have the resources to try out myself.
First a comment: I wouldn't consider a 2Gig course large ... but then again, am in the K12 world sooooooo. I've several courses above that 2Gig - largest being 7.7 Gig.
Now outloud ...
auto used to take backup preferences - general backup defaults.
What are those? include logs, histories, calendar events, etc. - keep logs for X days
Actually, in 3.9, auto has settings of it's own:
and also in a 4.0.4+
Number of courses?
Your 4.1 isn't actively used so do you archive your 3.9 - restore to new environment - then upgrade to 4.1? Then run auto?
adhoc task on the 3.9 look like? ditto for your 4.1dev.
How long does that 2Gig course take to backup IF you were to backup just that course from cli?
'SoS', Ken