I'm familiar with crossover from many arenas, one of the most prominent being from the Nine-Step program. Once upon a time I reached it, but every crossover point is based on assumptions and best guesses. I blogged about the financial side and some other aspects. Rather than dump over a thousand words here, I'll just provide a link.
http://trimbathcreative.wordpress.com/2012/12/22/crossover-into-a-new-world/
Crossover points sound like they are obvious events; but,
"At the moment of the crossover point, there is little confidence. Eagerness and anxiety are in balance as well. Optimism and pessimism can see both futures."