Two things different from 2008.

1. Spirit is in a much better financial shape.
2. They are desperate to maintain and grow capacity.

Eventually the F could and will happen if oil stays high enough, for long enough. Spirit does not live in a bubble after all. My guess is if we will be looking at oil above $120 over the summer perhaps they will have to reduce flying, and try to fly through the peak. But since everyone else (not just airlines) will do the same, the expectation will be that oil demand will drop and price will crash toward the end of the year.

So yeah I would not be surprised if they would ask for leaves and voluntary F or even mandatory by end of summer. But I highly doubt they would try to return airplanes. That was a big mistake in 2008. So if there will be F, I would say it will last much shorter.

Btw I have heard nothing about F yet. And yes, if Saudi Arabia and Kuwait starts to riot as well... oil may stay very high for a long time. Let's hope this will not happen. I am definitely worried about all that is going on over the ME.