^^ In answer to Cherryy:
The day before the SPs or SD for the team event is the ISU deadline for federations to commit specific skaters to competing. (Whether any federation voluntarily will announce its team competitors at an earlier date is a separate question.)
If a NOC/ISU Member has 2 or 3 entries in an individual OWG competition/discipline then the NOC/ISU Member must declare the Skaters/Couples to compete in the Short Program/Short Dance of the Team Event latest at 10.00 hours (a.m.), local time on site of the OWG, the day before the beginning of the first Short Program/Short Dance of the Figure Skating Team Event. For the 5 Teams qualified for the Free Skating/Free Dance of the Figure Skating Team Event the NOC/ISU Member must declare the Skater/Couple competing for the Free Skating/Free Dance immediately (latest about 10 minutes) after the conclusion of the last Short Program/Short Dance of the Team Event in order to ensure that the Team composition of all Teams are known before the beginning of the Free Skating/Free Dance.