User blog comment:Xilinoc/Ch. 542 - THE BLADE IS ME/@comment-5847836-20130619182602/@comment-8669536-20130621093949

Considering he could barely wound a Gillian in the beginning I severely doubt he has always been Stern Ritter strong, but I think he's that strong now and he might have been that strong since the Lost Agent arc or he might've gotten stronger during between the current arc and the Lost Agent arc.