This page explains the advice you should give to group travellers if you are a tour operator or travel agent.
For more details on group travel and a list of airports where this service is available see What is group travel?
If you are a tour operator or travel agent you should:
When you can, you should give the airport advance information on the passengers to help them to be processed quickly at immigration control.
If you are a tour leader travelling with a group, you should take the passengers to the immigration officer at the group travel point. Tell the immigration officer the purpose and length of the group's stay in the United Kingdom.