I know it's hard when everybody keeps saying this but - no easy way to answer those questions 'cause there's so much flux. A whole bunch of bases, a lot of them really small where a couple folks go out on FMLA and all of a sudden everybody's working 19 days a month. Then you've got the season fluctuations where flying varies widely from month to month. As sort of a very rough guide I would say most times senior folks can hold 16 17 days off but as soon as I write that you'll see a dozen posts from senior guys calling bu!!$hit.
As for Asheville I'd say it's very tenuous; it's a brand-new and a very small base & Allegiant won't hesitate to pull the plug after one summer if the numbers aren't there. This is a company that closed a base in LAX for crying out loud, so nothing's safe except LAS SFB & maybe IWA & PIE.