Anytime.
Again, wasn't following your threads, so don't know the desired geography, but I'd say either
- go to a regional where you can comfortably sit reserve in base as a DEC for 2.5-3 yrs (timeframe for those hired after you to get the hours, upgrade and be junior to you)
- go to a regional where you'll get current and fly a bunch of hours in year one and two, captain or not, and then start looking for a place to hang your hat - cargo or LCC.
Don't let the age discourage you. I've had two FOs in their early 50s in my class, no one looked funny at them.