Is it intended to run start() method of guarded task before guard?

In my case I'm using guards to check if task should run and I'm setting some values that guarded task may use.

For example:
(isPlayerVisible? range:512 outVar:"targetPlayer") interpose ent1Var:"targetGuardEnt" ent2Var:"targetPlayer"

Guard is checking if any player is visible and output visible player reference to blackboard. Interpose task is using this reference in its start() method to set up Interpose task. But because interpose start() method is run before guard I've got null ptr exception.