@Horst
Invite age dropping seems to of slowed down again now. I was expecting the 28-30’s to of opened up by now considering how fast it was dropping.
As I understand it, those aged 30-39 are all in the same vaccination cohort, whereas 28 and 29 year olds are in the next cohort (18-29). So in theory, they could have opened up to everyone aged 30-39 at the same time as they're all in the same position in the "queue". But then the system would crash due to sheer numbers; I believe that happened when they opened to the entire 45-49 group at the same time. So they have to stagger the invites for admin reasons but can move through them quite quickly. Then iirc there's a pause while they work through the appointments booked by that cohort before moving on to the next cohort.