Code:
Sub M_snb()
    [K2:K200] = [if(B2:B200="","",if(isnumber(B2:B200),B2:B200,date(right(trim(B2:B200),4),substitute(mid(B2:B200,search("/",B2:B200)+1,2),"/",""),substitute(left(substitute(B2:B200,"`",""),2),"/",""))))]
End Sub