Wisecrack? Habitual response is following it in West Midlands at first (9)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

( IT + TIC [habitual response] + IS ) contained in ( W [West] + M [ inital letter of {at first}] M idlands) – we have TIC ‘following’ IT when we read left to right.