I had some odd changes too.  Ran SFDC with no backups at PG/SG/PF/C, and one reserve at PG/SG and another at PF/C.  For some reason the reserve SG started subbing in like a backup.
I loaded up the lineup after the game it was very odd, the starting PG was added as a backup PG/SG, and the starting C was added as a backup PF/C.
Bizarre, and I'm certain i would have never set anything like that.
                                
                                
                                
                                
                                
                                
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