the only problem I have with the comic Data being B-4, is would he assume Data's rank? if they are treating him as the 'same' entity, fair enough, but surely he's a different being and should have to start from the bottom, therefore Captain is an unreasonable rank in the timeframe.
Is it any different to Captain Spock returning from the dead after three months?
Or Commander Spock returning to duty after "Spock's Brain"?
Or Captain Kirk after being split into two people?
Or Tuvok returning to duty after "Tuvix"?