It looks like there were 2 faults this evening. The first around 17:00 hrs, which they thought they had fixed at 17:30, but then the system went down again an hour later, as a safety related fault. I think it has all now been fixed and items held up in check-in areas are being fed back into the system . But clearly a lot of bags are being stored in various places around T5, including the BRF, and incoming bags are being brought in via 568. That's part of T5C so explains what you saw on the air tags. Given than almost all flights have left T5 today, the blocked bags will probably only fly tomorrow. The BRF (baggage reconciliation facility, an emergency warehouse) is being staffed overnight.

Short version: If you were departing this evening (Sunday) or connecting, there is a high chance your bags are being stored overnight in T5.