Trades with "expired" items are allowed. i.e. winter crates, fall crate, eerie crates, etc.

They must be stored on an account the DOES NOT LOG ONTO TF2

I believe as long as you dont log on to TF2 they wont disappear, but please get an outside opinion, I am 99% sure they wont disappear (I have spells and fall crates stored). Trading outside of in game TF2 should keep the items in the bps.

As a general rule, not including Valve intervention, changes to your BP only occur upon logging in to TF2. If you want to keep crate 6s or another very rare item, the use of alts prevents them from expiring. You can log in as your alt on Steam with no worries, but if you open TF2, the items will disappear, so exercise caution.

I am wondering the same thing.

Nobel and Champelliot didn't really answer the question.

What Ziddia is asking is:
I store items like a crate 6 or a spell on an alt account.
If I want to list one of those expire-able items on TF2Outpost, am I allowed to log onto TF2Outpost with my alt account and post the trade with the expire-able item under an alt account? or do all of my trades need to be listed under my one main account?

Thanks

I asked a similar question recently and I was told it's allowed. Just don't relist the trades on both accounts and you'll be fine.