Lovely! The choice of Augusta's point of view for this fic is inspired. You're got the summery atmosphere and the unexpected, enforced holiday, and the trip to the seaside, and yet their task is always there lurking in the background, a reminder that this isn't a light-hearted expedition. Because Augusta's not well positioned to fully understand just how serious it might be, we can move back and forth between her enjoyment and our own awareness of the dangers. (At least I did.) Very nice. The May-December relationship between Severus and Amelia* also gives the whole story a sense of hope against the odds. Lovely. Enjoyed! M.
* Actually, I have no idea how old Amelia's supposed to be in 1980, but junior Severus would make anyone feel December-ish.