As the screenshot suggest, the timer was started before the first portal was broken.
Attachment 25408
Printable View
As the screenshot suggest, the timer was started before the first portal was broken.
Attachment 25408
Tried to recall the situation and recalled the warrior did a windmill but not near the portal and it never break the seal.
Something I noticed from running 2 toons at the same time on different devices was that when there's a group of you moving through a map you each see a slightly different formation of toons due to the lag between your device and the main server, perhaps this could be an explanation.