The 18 day will be fixed, but while training has you as a new hire for sim and basic indoc, you are pretty much owned and must train when they say you will train. I believe that at least they must give you any days that you worked over 18 in a month the following month as extra days off. When I started I was run in the sim first and then after 4 days off I was right into indoc. I did get a few weeks off before aircraft training, but I'm not sure how much was due to owed time off versus very poor scheduling practices. Most get a bit more time off between indoc and sim, whichever order the company puts them through.