Paying Ultron level 5 and the Thor Sentry node didn’t unlock Ultron for another round once defeated. Didn’t see anyone else report a similar issue so I figured I would post.
I just had this same thing happen to me in round 6 on a QS essential. The node showed as complete but Ultron was sill locked and the timer read 8 hours 17 minutes. It resolved itself after about 10 minutes and now the main fight is open again. I hope this is the same for everyone who experiences this, that way it is only a minor inconvenience.
I had a similar issue twice today. Both were against the Quicksilver nodes, it cost me a battle against him as when I moved on to the next node, it was only unlocked for an extra four attacks.
Yes, it eventually unlocked for me. Might have just been a slow server connection or something.