Hey, first let me say I love this story and look forward to many more wonderful chapters. I'd especially like to see some sort of flash back with Dumbles during WW2 meeting the Capt.
It could happen after he is introduced to Harry's physical trainer. It's not all that farfetched really. If Riddle who avoided the Muggle world like the plague (unless he was destroying part of it) encountered Union Jack, a younger Albus almost certainly was involved in some mission with the Invaders.
Also, as a thought, for Harry's project I'm thinking something like a magical search engine. He could create something the links into the crystal stored books of the Ravenclaw Library, and spontaneously generates a full index for everybook in it. There after 'claws could locate any topic by simply entering the keyword some how (spoken or written on parchment?) just like googling, and find themselves presented with a list of not just every book the topic can be found in but a list of page numbers where it appears in each book.
Author's response
- Albus accompanied a the Invaders on a most specific mission, as will be revealed in 4th year
- That's pretty much what I'm going to do.