In her case, she doesn't have a good enough reason - she just wants to go.
If she'd talked to me first, I would have strongly have advised her to dish out the extra £200 and go in person...to me, postal apps are for people who either don't have a straightforward app or aren't in any hurry to go anywhere. She's been in a rush to get this over with since she became eligible at the end of August. Most days, she's been fairly ok about the wait... the last few days, she's just gotten frustrated.
She also said she felt bad about calling. She reckons the people who answer the phones get to deal with people like her way too often, and they just couldn't really tell her anything...