It's clear when rule 22 turns off but it seems to me less clear when it turns on, and I can see this being a cause for controversy in some incidents.
Rule 21.1 imposes a keep clear burden on a boat "when sailing towards the pre-start side of the starting line or one of its extensions...". When does this obligation commence? Is it when the boat departs from her proper course with the intention of returning to the pre-start side of the line? Or only when her relative bearing to the line is less than 90, such that her motion is toward rather than away from the line? For example, if an OCS boat on starboard tack on an upwind leg falls off to a course parallel to the line, must she keep clear of port tackers under 22.1? Or does she retain starboard right of way until she falls off further?
Likewise under 22.2, at what point is a boat doing a turns penalty "taking a penalty"? Is it as soon as she begins altering course? At the first tack or gybe? As soon as she starts sailing to get well clear of other boats (I think not, since 44.2 says a boat takes a penalty "after getting well clear)?
I didn't see any cases or US appeals dealing with rule 22, which kind of surprised me.
What do you all think?