Something tells me that this isn't supposed to happen. I've attached a screenshot of the issue because that's easier than explaining it. For the record, this happened around 4:30 Pacific Standard Time immediately after I completed Tomb Of Tvericus on the test server. In addition to this, it was also impossible to progress to the next stage. Refreshing the game and logging in again got around it though.
Known bug that will be fixed next build. It's calling the League Completion animation instead of Renown Increase animation. Just continue to refresh whenever it happens.