In the corporate world you are really being paid for being available not to fly. At least that is the way it is viewed by most owners or operators. Your owner regardless of what they say has "bought" your time for the year. Similiar to how ailines buy your 1000 hours of flight time a year. That is the main reason my new job has hard days off, so I can do what I want, when I want, and can fly for whoever or whatever I want as long as it does not interfere with the 135 rest and flight time rules. Don't say they don't exist, because they do. They are just extemely hard jobs to find because nobody quits them. I have been trying since 2001 to get hired by my current company and finally did earlier this year.