Current sea service letter rules

A question regarding sea time letters from employers. I usually only turn in time upon renewal or upgrade every 5 years.

The old guideline letters vs new guideline letters I’ve found address 12 hour days differently.

My time is on ABS class but uninspected vessels so no COI. The guidelines seem to want the watch schedule printed on the COI or manning certificate. We don’t have either and foreign flagged.

I’m writing a letter for the office and using the older format that says, master or mate upon international waters standing 12 hour navigation watch.

Does this still apply at 1.5?

Thanks in advance.