They are in a document called Jury Policies https://www.sailing.org/41703.php

Which can be found (along with other useful docs) in the International Judges Document Library: https://www.sailing.org/raceofficials/internationaljudge/document_library.php

Huh … found this interesting … from the Race Mgmt Policy

12.1 Flag I (RRS30.1) and Flag Z (RRS30.2) will not be used.

Thank you Andrew and Graham. Great sources of information. I learn something new every time I look at this forum.
Ange, I observed this at a recent International event and I thought it was harsh not to give the competitors at least one chance at "I". It ended up on the first day of the regatta a very strong current was setting the fleet over the line causing crowding and stalling at the gun. One of the very serious contenders for the regatta was "UFD" two or three times the first day. Any idea why this would be a policy?

Any IRO’s on the forum who can weigh in on the reasoning behind WS wishing to exclude 30.1 and 30.2 from their events?

I'm not an IRO, but I can offer explanations.

I Flag.  Despite being referred to as a 'penalty', an I Flag start is not a penalty:  it is a 'traffic control measure', which decongests an unavoidably crowded starting line, and can facilitate accounting for OCS boats returning.  It has undesirable consequences on other than a short starting line, in it induces boats to crowd the ends, because the middle of the line, does incur a penalty on an OCS boat in having to sail further towards the ends, than boats nearer the ends.

Z Flag.  Olympic and WS Championship events are predominatly one desigh, and given the marketing department's insistence on instant gratification, there is no point in replacing turns penalties, the effect of which is immediately apparent on the water, with scoring penalties, which require after race calculation.