Mosaic Award Flight Point Difference
 

I booked a flight for my family for august. Let’s say in the future, the same flights become less points to book, can I call and get credited the difference back to my account ? I have mosaic status via credit card spend.

for example, I used 80,000 points but now the same flights are 50,000 points. Will I be able to call and get 30,000 points refunded ?

Yes they should be able to do that for you over the mosaic line. And if they can't, just have them cancel the flight and rebook it at the lower points cost. No change fees either way.

when an award flight is cancelled, are the points redeposited immediately or is there some sort of delay?

The points are redeposited immediately.