rman recover copy seems to be creating endless backups

Hi,

We're on 11.2.0.3 on RHEL 6.2

I have 3 databases happily doing rman backups with

run { allocate channel c1 type disk;

recover copy of datebase with tag 'SID_reco_1' until time 'sysdate -3';

backup incremental level 1 for recover copy with tag 'SID_reco_1' database;

}

However a fourth database ( using the exact same script ) keeps generating backup after backup after backup and there's a couple of month's worth choking up the FRA and constantly threatening to fill it.

This is a fairly simple setup with no catalog. I'm sure the answer is annoyingly simple - but I'm out of ideas as to how to fix this ... and out of diskspace to throw at the ever increasing FRA.