I ventured into TSR yesterday, and saw that a lot of state school students have access to interview training this year. Have any of your DC's got a slot? Looks like you had to book in advance, so too late now, but a good indicator of extra assistance available.
DD has a practice interview today with a parent volunteer, so that is nice to have too. They are doing it over zoom, to replicate the experience as much as possible. It will be interesting to hear how she gets on.