Probably makes sense to take the charge now to reduce income tax liabilities.

Anyway, I'm not surprised at all that they're looking at used aircraft. DL has a history of acquiring used birds on the cheap... just look at the MD90 and 717 fleets. Just have to make sure the maintenance history from the previous owner(s) is up to par on them, especially with the widebodies or they can become a big MX liability.