What is the official rule on alternate team members?
There is no official rule on alternate members. Guidelines suggest that alternates participate when one of the 15 regular team members is absent the day of the competition. Alternates may not fill in if there is a schedule conflict or if the schedule changes on the day of the competition.
Some tournaments restrict the number of alternates per team and sometimes allow them to participate in trials events and to drop off impound items. A common number of alternates for a team is 5. Many tournaments issue and require regular team members to wear wrist bands so alternates do not accidentally cover for a late member.