Well, assuming you're a CFI with no other experience, this might be premature to ask, but for the purposes of education..

there's only one base as of Dec 2013, which is HNL, and depending on equipment, the reserve either goes junior or senior..

On the Worldwide fleet, it's junior and you could be on reserve for a two months or 2 years, depending on how much hiring occurs after you.

On the interisland, I can say that after 8 months, I still can't hold it... it goes quite senior for the most part.