We were already aware that Becky Lynch and Charlotte Flair were all set to face each other at Fastlane. However, early in tonight's show it was expected that the match would be for the vacant RAW Women's Title after Ronda Rousey walked out during the previous week's show.
During the contract signing though, Ronda came back to the company and got her title back. As a result, the match was changed a bit. If Becky wins she will be added to the title match at Wrestlemania. If Charlotte wins, it will be Ronda vs. Charlotte solely.
It should also be noted that Rousey did a complete heel turn, directing her anger at the audience.