rlsbutler,
The ferry flight was routed SBSJ-SBEG-onwards (probably KFLL). Cruise climb is not an usual procedure on this particular airspace, and I doubt the pilots of the Legacy had this in mind.
RiverCity,
At the time radar contact was lost with the B738, it was around 1940Z/1640LT, so not dark yet. What is really puzzling is the fact that no information on the ATC actions prior the accident have been made public.