Diana Wynne Jones Love-Week continues at Book of the Day with The Merlin Conspiracy.
Merlin isn't a who, though,in the Islands of Blest. It's an office, recently vacated and now occupied by someone who is up to no good. Roddy, a young page travelling with the King's Court, must discover her magical powers! And foil the evil plot! While not-flirting with an attractice teen boy from another universe!
Nick Mallory is the teen boy in question, who gets himself lost among worlds and embroiled in the mess. Nick and Roddy take turns writing chapters. Good voices.
And again with the Britishness: Nick at one point says 'it was like a whole train of pennies dropping on my head.'. Now that's a nice image, and not one you'd find in an American book.
This appears to take place in the Chrestomanci universe, but that's not really laid out - and the book suffers for it, I think. I prefer when things make more sense and we know the mechanism for the magics. The time travel really threw me for a loop when keeping track fo what was going on.