Does Ticketmaster release more tickets when the day of the concert nears?
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When primary market ticket sellers release tickets for sale after the published on sale date is not generally public information. This is because scalpers could use the information to buy tickets and primary market sellers sell tickets when the come into excess inventory. The best times to look for tickets in my experience is the few days following the on sale date around 10am and the seven days leading up to the event date, again around 10am. Monday and Tuesday seems to be pretty good days if the show is on a Friday or Saturday in that same week.