When using Alchemy to create a Lynchpin that casts a sustained spell, once the spell is cast, how is the spell sustained? Does the lynchpin itself sustain the spell? And if so, for how long?

I know they meant for systained spells to be used, since their example includes a sustained spell (shadow).

Edit (Nevermind, this was a simple question answered by Lobo).

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If the spell is sustained, it lasts for (Potency) minutes (or in
the case of a permanent spell until it becomes permanent).
There is no Drain in this spellcasting because it
was already taken by the alchemist; likewise no Edge
pool can be spent on this spellcasting.

This makes me think there's a wealth of possibilities in Influence preparations.

Pretty solid for combat boosts like improved attribute and combat sense.

Simple action trigger improved attribute agility, quick draw shot with pistol in one pass for example.

Yeah - set up some good buff preparations in advance, activate them as needed.