There might be, but I'm not aware of any.
The only thing I can think of, is to create functions to deactivate each group, and then choose which function to run according to some expression.
Something like this:
+ On Loop "Deactivate Group_A"
-> Deactivate Group A
+ On Loop "Deactivate Group_B"
-> Deactivate Group B
+ Something happens...
-> Run fastloop "Deactivate " + <group name> , 1 time