These time are all estimates:

12.30 – 13.30 Marriage service

13.30 – 14.15/30 meeting and greeting with mulled wine, photos

14.30 – 15.00 Drive to Reigate

15.00 – 15.45 Drinks and canapés

15.45 Sit down to meal

18.30 Speeches

19.00 Cut cake

19.30 Evening guests arrive

20.30/21.00 Evening buffet