What is the casting time of an extended spell imbued into an item?

Question

There is no restriction on the casting time of spells that you can imbue into an item with Prime 3. For permanently active effects this is not a problem, but in the case of conditional powers I am unsure about the time required to activate them.

A trigger should be an appropriate instant action [..] When the trigger is activated, the imbued item’s spellcasting dice pool is rolled. (MtA 84, emphasis mine)

Does imbuing a spell into an item enable you to effectively turn a spell requiring extended casting into an instant one? Is the pool rolled only once, regardless of the original casting time?

Answer 1

Reading it up, the Imbue Item spell makes it clear, when creating the imbued spell "The target number is equal to the successes required for all the spells imbued into the item"

You effectively cast the spell once (with duration set at that time), in an extended casting.

Later you can activate the effects of that spell, however regardless of the duration used in creation - often indefinite - the effects only last 1 turn or 1 scene/hour (depending on the spell it is based on) before needing to be reactivated.

This effectively gives you one ritual lenght spell which is pre-cast and can be activated instantly with potentially new targets each time.

Only one copy of the Spell's effect can exist at a time, but the imbued item's trigger effectively allows you to alter spell factors of an ongoing (imbued) spell (except duration which is explicitly set at 1 turn or scene).

NB: for spells that have a base duration of lasting, this means the item can only be activated once. The lasting effect remains forever. Though the RAW aren't clear, the merit only explains what happens for spells with duration: transitory and prolonged, it could be argued that duration:lasting spells are not possible to imbue.