From RSLogix 500 help file:
"You can use the reset (RES) instruction to reset a sequencer. All control bits (except FD) will be reset to zero. The position will also be reset to zero. Program the address of your control register in the RES."
Resetting won't change the outputs, though. You'll need to clock to position 1 to do that.
Since the SQO is basically a move with mask (ie retentive) its outputs won't be affected by an MCR zone.