Yeah umm... if she wants the opinion of doctors and no hearsay, why isn't she asking her own doctor?
Here's my hearsay and guessing and speculation
I'd imagine if she wants to change the time, she just picks a day and starts taking the pill at 7am instead of 2:30 am or whaever. And use condoms for a month or so after she makes the switch, just to be sure. Or something like that