Phantoms can deliver touch spells, but with a unique limitation: "The Phantom can't hold the charge of the touch spell cast by the spiritualist using this ability. If the spell is delivered to the phantom, it must touch the target or the spell is lost."
But what if the Phantom is given a spell that is designed to have multiple attacks over multiple rounds, like Frostbite (which does not have a specific duration, just "up to one time per level") or Calcific Touch (which does have a specific duration in rounds)?
Is the spell still only deliverable for one immediate action? Does the spell keep functioning until the Phantom misses?
(I know these spells are not on the Spiritualist list, but a Death Druid could have his Phantom deliver Frostbite.)