Oh, gotcha, I didn't read the post through enough. In this case you need to make a caster and target buff, where the target calls back to the caster using FirstSpawnerNoLongerHasBuff/LastSpawnerNoLongerHasBuff to see if the buff has ended, as well as make the caster buff have a finish condition of EnterHyperspace.
That should decast it on the planet while using the caster as the 'trigger': if the caster makes a jump, the node's gone.