SGA: Postmaster replaces old items with new ones; never let your Postmaster get full with good stuff in the top slots or you'll lose it.
I knew the postmaster had an item limit of 20, and I was trying to take advantage of that as I was stockpiling exotic engrams/weapons to use for 1:1 infusion following the April update. What I [i]didn't[/i] know is that the Postmaster [u]replaces the oldest item in your inventory with the newest[/u]. I was actively maintaining my Postmaster inventory so it was only good legendaries or exotics... all stuff that I wanted. So it really sucked when I found out that almost all of that stuff had been replaced with rare blue engrams/items after I did some Strikes/CoO. [b]There should be the ability to lock stuff in the Postmaster so that it's not replaced, just like you can lock an item so you don't accidentally dismantle it[/b]. Or a hierarchical system where exotics are always held, then legendaries, then blues/greens. Makes no sense to have a system that can replace an EXOTIC item with a RARE item.
Postmaster isn't an extended vault.
They've reminded us about this a number of times now
It's fine for a short term thing like if you're running a bunch of heroic strikes for a few hours and you have a little bit of overflow.
But long term, go to the community areas and pick stuff up. Or else lose it