Question: Re-Crew Abandoned Vehicles and Weapons

[shahadi]

Reading the game guide I understand the "J" key is used to join a crew with it's vehicle or weapon. Now, I need to know if a crew can be separated from a vehicle or weapon in deploy without loading onto an air transport, how many turns before the crew is joined, how far apart may a crew be separated, and finally if a crew can be joined by the AI?

Two crews separated from a BMP-1 and a T-72, with the BMP crew in the same Hex as their vehicle and the T-72 crew one hex away.