I just upgraded the plugin from 0.17 to the latest 2.7.0.

For a matrix job (multi-configuration job),
back in 0.17,
I was able to select "Execute script on":
MATRIX - executed for matrix parent job only
AXES - executed for each matrix axes jobs
BOTH - executed for both matrix parent and axes jobs

But in 2.7.0,
I don't see such configuration anymore.
I see only "Execution is limited to":
Master
Slave
Both

When selecting "Master",
the execution still runs for both matrix parent and axes jobs.