Relation: "Is less than"
That will now alert you to when you can dispatch below 35%, I also add in an exception to not alert me if it's already done so a few seconds ago. This is useful for when you have many targets around and dont want it spamming you each time you target a new one.
I also add a subtle tone to the event trigger as well, this is done easily by finding the trigger in your list of triggers and pressing the screwdriver and spanner icon and looking under sound.
Or do what I did, select Spell Cooldown, select Dispatch, and tick the button Usable.
It will trigger when below 35% or on Blindside proc, and when the target is actually attackable (hostile).
Downside is that one of the conditions is also enough energy for you to use Dispatch, so it will activate when the hostile target is below 35% and you've got at least 30 energy. In reality, there won't be any delays, since you can't use dispatch while below 30 energ anyway.