So xur is coming tomorrow, and if you have some exotic shards and some exotics that you want to upgrade, you're probably gonna want to re-max-out your exotic as fast as possible right?
If you save up your finished bounties today and dont turn them in, you'll be able to turn them in tomorrow after you first upgrade any exotics to get lots of XP towards them, plus the xp of tomorrow's bounties.
-
If you are on during the reset you can turn in everything you saved just like you mentioned. Grab all the new bounties for the day and complete them and turn in. Here is the tricky part. Turn off your counsel then turn it back on and you can get all your bounties again. Extra score!