An easy way to tell is just look at the Progression percentage at the top left of the screen.
At the start of round 2 it will be on 20%, at the start of round 3 it will be on 40% etc
For example:
After round 1 Schemin' phase it will be 10%
After round 1 Stealin' phase it will be 20%
After round 2 Schemin' phase it will be 30%
After round 2 Stealin' phase it will be 40%
So if you load up the game and it says 80% then it will be the 5th round Schemin' phase.