Q: If someone plays Taskmaster on their turn, and gives me a Surprise, do I play using the out-of-turn effect, since it’s not my turn?

A: So, the way to think about this is that, even though it’s the Taskmaster’s turn, you are being that person’s executors, and what you’re executing is the in-turn play of a card. Given this, if the card you must play is a Surprise, you follow the “During your Turn” part of the card.

Also remember this: the out-of-turn function for a Surprise is (almost) always in reaction to some other triggering card play which is being canceled, and it interrupts someone else’s turn. In this case, there is no trigger; no card play to nullify, and no “Surprise!” interruption. In this case, you’re not interrupting anything. You’re required to play this little mini-turn, deliberately caused by the active player.