Periodic GC without watermark

We're about to switch to using the S3 backed datastore in Peergos. However we would like to remove the storage limit, but still have periodic GCs (S3 is practically infinite, and we have external access control and limits per user which we enforce).

Essentially I want to set the GC period, but have it always run at least once in that period and remove most if not all of the un-pinned stuff.

My understanding is that this isn't currently possible because GC only runs if the GC watermark is exceeded?

Personally I think it is counter-intuitive that the GC only runs if both conditions are met, based on the config names I would guess it runs periodically *OR* if the storage watermark is hit, not *AND*. Either way, this should be documented here: https://github.com/ipfs/go-ipfs/blob/master/docs/config.md