Just tested this and works, landed after approx 30 mins but can take up to 24 hours. My voucher states expires mid june so plenty of time to redeem it.
This voucher entitles you to a complimentary glass of wine, with the purchase of a main meal.
Terms & Conditions:
This voucher entitles you to a complimentary 175ml glass of house selection wine at any Miller & Carter steakhouse with the purchase of one main course. Voucher is not valid with any other discount or promotion. Offer is available all day every day. Offer is not valid on Sunday Set Menu, Thursday date night menu, fixed price lunch menu and young guests menu. Only one voucher is valid per guest. Voucher is not valid in conjunction with any other offer, voucher, discount, privilege or set menu. Not valid with Festive menus. Not valid on Bank Holidays, Mother's Day, Father's Day, Christmas Day, Boxing Day, New Year’s Eve or Valentine's Day. Alcohol-Free cocktail is available upon request. Voucher can only be redeemed once.