Congrats and good luck at ASA!
Do a little research on Custom, and I'm pretty sure you'll see the answer. Even if the money is there in 18 months, you might not be. They have quite a reputation. I've not worked there myself, and have not even considered it, even on the worst days of unemployment desparation.
I'm trying to avoid bashing Custom, reporting only the facts as I know them. ASA folks seem pretty happy, get time off, and treated with respect. I've got an app in there right now, and would gladly take their pay vs. Captain's pay at Custom. Custom has hired captains of the street, and I imagine will continue to do so. Factor that into your upgrade hopes. Regarding time in bigger type, I'd say big deal. Time under 121, and "quality time", glass time, and jet time are more important than size.
Good Luck