Straight from the patch notes: http://steamcommunity.com/games/221100/announcements/detail/175957169845835283
"Known issues:
Persistent items & storage are disabled server side pending hot fix to stable branch
New:
Server: Persistent item support (disabled for this update)
Server: Persistent storage support (disabled for this update)
"
Persistent loot isn't yet enabled in stable, hence why your tent disappeared. Loot still respawns, though.