However, after featuring just once for Craig Elliott's side - the 3-2 county cup win at Lincoln United - he left to take up the new role of set-piece coach at the Championship club.
Butler is understood to be helping out at League One strugglers Doncaster Rovers, where current Boston United midfielder Paul Green is fitness coach, but only in an unofficial capacity.
He is the manager of the Doncaster Belles ladies team who play in the same National League division as Posh Women.
Posh are not expected to replace Butler with responsibility for set-pieces falling to coaches Matthew Etherington and Mark Tyler.
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