The short answer is, enhancements to the boolean logic in the trigger system are coming.
This is one of the most requested features on the community, and we’re finally getting to the end of all the back end / enterprise work that has kept our development team from knocking out these hotly community requested features.
That said, sometimes the solutions are a little hacky, but for certain types of conditional statements, people have been able to achieve these using multiple IF/THEN statements, and when time is involved, using the Cayenne Scheduler in conjunction with the Triggers feature.
Have a look at this idea from an older thread on the same subject to see one way this could be accomplished: Conditional triggers - #2 by bestes