Awesome update! If you've answered this and I missed it then I apologize but have you checked the condition of the contacts and surrounding area on the bird?
Thanks I've looked at them the best I can, using an illuminated "loupe". They don;t appear to be obviously damged. and I've also had a spare battery connected and the P4A flying with it, and there was no obvious problems. I did expect the contacts in the drone to be affected, but it doesn't seem to be the case.