Yes, they still operate a couple of Convairs.
No, there are no direct links to move to the Boeing fleet. Technically it's not a DHL company; it's called SNAS. Therefore, there are no natural progression to the EAT or DHL Air 757 fleet. There are at present no plans to replace the SNAS 757PF sadly lost last year. Volumes are picking up dramatically in the ME, and the 757 that used to do the BRU-BAH-DXB-(BGY)-BRU run has been replaced by an A300-600F AND (for the war-time moment) a DHL Airways DC8-73F.
Maintenance is to airline standards (what did you expect, hi-speed tape?), done by mainly brit expats.
DO is still PB, and he's still very much in control.
Whilst there is a fairly large number of expats flying for SNAS, the tendancy seems to be moving towards local hires. If the choice is between an expat and a local, well .........