If you take a job through an agency it's common to have an arrangement where the airline pays your 'per diems' or some such 'allowances' while the leasing company pays your main salary.
I've never been let down by the leasing agency (prime salary payments) but I've often had to hassle the airline accounts people for my 'allowances'.
If I was taking another contract job I'd make sure to either avoid the allowances type deal, or else get a clause saying the leasing company would pay it in event of any delay or default.