Wales U19 international Bostock added: "I remember him (Downing) coaching me at under-7s so it's great to see Leigh step up to the U21s.
"I like the way he plays because it compliments me, gets me on the ball a lot - as we saw in the Youth Cup last season - and it's really exciting times, so hopefully we can play some good football under him.
"Wanting to play senior football is the boat me, and a lot of others, are in at the moment but whatever happens, I just want to play my best football, show what I can do, score some goals and get assists too along the way.
"It's always nice to play Villa, everyone here is up for it and it's another chance to perform and, hopefully, get three points everyone can enjoy."