How long has the instadeath invisible wall been preventing freeps from claiming the relics?

Tonight five brave freeps dusted off Gladden's moors map, merrily flipping everything in the delving and then turning the map blue. To end the night we fought our way thru to the top of the creep stronghold to claim the relics... we made short work of the bosses and sent in our runner to claim the prize.

ONLY to find that they are now protected by an instadeath invisible wall.

no creeps... no traps... no... just an instadeath invisble wall just inside the trophy room no matter what path we tried.

*sigh* A very disappointing end to the night.