How do they determine who plays on the first day of the Stanley cup playoffs vs starting on the second day?

The schedule for the Stanley Cup playoffs is determined by the NHL based on the standings at the end of the regular season. The teams that qualify for the playoffs are seeded, and matchups are established according to their rankings. The league then creates a schedule that maximizes viewership and logistical considerations, determining which games will be played on each day. Factors such as travel, arena availability, and TV broadcasting rights also play a role in deciding the timing of the games.