World Sailing's Sailing Instruction Guide, Appendix LG, includes the following:
12.5 If any part of a boat’s hull is on the course side of the starting line during the two minutes before her starting signal and she is identified, the race committee will attempt to broadcast her sail number on VHF channel. Failure to make a broadcast or to time it accurately will not be grounds for a request for redress. This changes RRS 62.1(a).
I personally have not seen this in use.
World Sailing's Race Management Manual does not address it, the RYA's Race Management Guide does not mention it. US Sailing's Race Management Handbook, page 257 "Hailing a boat before the starting signal is bad practice, no matter how far over she may be. Doing so requires changing, in advance in the sailing instructions, not one but two rules, 29.1 and 41. Think about it! Starting is a major part of racing, and to help those not adept at starting will negatively affect those who are."
Add in a penalty (I, Z, U, B) and hailing before the start is not possible in my mind. Which would seem to indicate to competitors if 12.5 is invoked starting penalties will not. be used.
Has anyone seen or used LG 12.5 invoked in a sailing instruction?