Blue tit and Great tit fledging behaviour

We've had two nesting boxes occupied from March to a couple of days ago with nests of great tits and blue tits. I've posted a number of videos in the hello section of the blue tit nest box.

Both nests have fledged in the last couple of days. Looking in the garden, I haven't seen ANY of the birds. Is anyone aware of how they'll behave and live? Is there a good chance I'll see any of them in the garden again, or will they probably fly away to new homes?

Question 2 - is it recommended to leave the nests exactly how they are now, in case of a second use this year for another brood.

Thanks for any responses.