The inner gate at Cear Berkstead was repaired despite the keep never leaving "Under Siege" status. It was displayed with flames on the war map constantly (Updating RW map frequently to make sure it did not leave siege status), no siege rewards were granted to players who participated in the fight, yet the inner gate could be repaired despite the siege status.
I taunted guards on range to make sure the keep could not leave the under siege status either, to prevent repairs.
Yet, the inner gate was back to 20% because repairs could be made. Seems like the "under siege" flag is bugged or runs out very quickly under certain conditions.