Yea, I'm hoping I'm wrong, I could use that 100 pounds, those last 4 Six/Evelyn stories are calling out to me (At least the first one is a Companion Chronicles and only $7.99 download)
Oh, and it is a cracking good story, too! Just when you think you know what's going on, it twists in an entirely new direction ... that makes perfect sense with what happened already. It's also one of the few CC's that use the format *well.*
I mean, all of the CC's are the companion telling a story of their adventures, to a second party. Some do it better than others. This one has an actual reason for being a CC.
It can be listened to at any time without spoiling any of her other adventures with the Doctor.