So, it was an offside pass, and an offside pass isn't a foul, so under 1.5.1h,
Time starts:
when the ball is snapped after the penalty application for a
foul that occurs after the 3MW...
So time would start on the RFP.
Nothing get's a rule stuck in your head like screwing it up the first time

That's how I've learned quite a few rules in both basketball and football