Time to Investigate

Satisfied as best I could be with how I looked, I walked over to the postroom counter. It was about waist high, with slits in it, one for Internal Post, the other for External Post. Above the counter was a metal shutter (with a sign on it saying. "Gone for training. Back in 2 hours.") separating me from the other side. Well mostly anyway. The shutter had obviously been pulled down without much concern for it closing all the way. It was resting about a foot off the top of the counter, propped up by two squat cardboard boxes.

Time to get my clothes back! Ok, let's see what we've got here... time to apply some of that middle manager thinking, Ren.

I looked around the room and through the gap in the shutter.

The post cart's clearly not here. Neither is the postwoman. Thank god.

Which means she has the cart with her...

On another collection route?

And why would anyone take a full cart with them?

...So she emptied it...

Therefore the envelope is... HERE!

D: THAT'S middle management thinking?!

A: Indeed! I'd call it jumping to conclusions.

I bent down to look inside the slit marked "Internal Post", inadvertently exposing my ass to the, thankfully, empty room.

Maybe she just posted it through here and-

I saw it. My envelope. My envelope containing my long-lost clothes!

OMG!! THERE IT IS!!

A: LAAAAA!!

D: Oh for the love of all that's unholy... will you stop that heavenly choir stuff PLEASE!

A: Cope. It's what we do.