Sounds like you have to decide whether you want to fully commit to the airlines. If you do, and are prepared to do what you need to, you can still get hired at age 50.

But in your shoes with nothing even resembling turbine recency, you're probably going to have to work for a regional or a comparable civilian gig first.

If you're just waiting for the majors to call, probably not going to happen. That might change in five years or so, but by then at age 55 your seniority cost/reward equation will not be looking too good.