Yesssss, I love how heel-face-turn Erich is still an Absolute Weirdo, just a friendly and helpful one now. And Biggles loves playing the game too.

Algy et al: someone invites you to a meeting via anonymous note slipped into the post, why are you going, have you lost your mind
Biggles: hmmm? *already pondering what he's going to wear*

I am also very fond of Biggles's later reactions.

He's just so desperate for ANY hint of something Erich wants (that he'll accept) so Biggles can give it to him!