Docucolor 242, Cyan Streaks

Hello All, Printer was working fine, very good/clean prints until yesterday then started leaving blue streaks, today called non xerox tech who cleaned machine, that seemed to work but after printing about 100 pgs of almost solid green 100lb gloss cover started to print the inside pages and problem came back, not sure where to go from here - any advice, direction to look etc appreciated, thanks

 

Looks like a bad (C) drum

Is it marking on the lead edge or it in the process direction?

 

Thank you InterfaceP , problem solved, still new to this business so thanks again for the advice