Gametime keeps selling till 60-90 minutes AFTER the game starts. Stubhub and
Ticketmaster used to be two hours before first pitch, but they've gotten laxer in the past few years, depending on the team, and it now appears they all keep selling well into the game as well (eroding GameTime's competitive advantage):
Instant delivery MLB listings on StubHub are available to buy until the start of each game. You can buy tickets for some clubs after the game starts. Up to 30 minutes after the game starts Chicago Cubs Kansas City Royals Los Angeles Angel...