Well, it does let you, but it doesn't seem to "take." I did this for mrs. brp who got a new passport. She entered it into her profile but, of course, it did not transfer over to existing reservations, and I forgot to do this until the day before. It showed correctly everywhere, but OLCI still flagged a mismatch.

Of course, there international OLCI has been so hit-or-miss for us, that it could well have been something else

Cheers.