As Virgin have already stated, it's best not to email. They will contact your daughter (Probably soon), when they have allocated her to a course, and cabin crew courses generally speaking run between January-June, unless of course like some airline like BA/Ryanair for example run all year.
Don't worry about notice, they would have asked your daughter in her interview what her notice period was, and will stick to that, they generally allocated courses no less than a month in advance, so she will have a months notice.
Best thing to do? Nothing, I completely understand how difficult it is and how impatient you can get, but there is nothing you can do other than wait for them to get in touch.