In "Blue" when Lister is reminiscing about the locker room game, we see his flashback to what he describes as "Red Dwarf in the early days". In the flashback, Rimmer is wearing the blue uniform that he received when made hardlight in "Legion".

However, a few episodes before "Legion" in "Psirens", Lister forgot where he parked Red Dwarf and it was lost. It had not been recovered by "Blue", and so there was no point in time prior to "Blue" when Rimmer could have worn the hardlight uniform in the Red Dwarf locker room. The flashback could never have happened.