Alternate drop 

Alternate drop service is where two (or three) menu dishes are chosen by the hosts in advance. People are served each meal, alternatively I.e. Chicken, beef, chicken, beef etc. Generally diners are free to swap meals on their table if someone else is willing. Alternate drop is commonly used in Australia and New Zealand and it's quite popular at large events instead of buffet style or basic menu options for each guest. Vegetarian guests, or those with dietary needs usually receive a different meal.

The wedding catering is alternate drop, main course is either salmon or beef.

Alternate drop by JJAustralia September 14, 2016