Heading to Vegas for ME, how late can I buy a seat?

[Chapdoggy]

This was the latest as of two days ago from the WSOP Harrahs official announcement

"As of July 23, more than 6,100 players had pre-registered for the upcoming $10,000 No-Limit Texas Hold’em World Championship. The amount surpasses last year’s record of 5,619 entries, ensuring this year’s Main Event, which starts July 28, will be the largest and richest live poker event ever held.

Tournament organizers scheduled a four-day start for the event to accommodate the enormous demand for seats. Registration continues around the clock at the Rio until July 28, at which point – if seats are still available – players can register on each start day until the first level of play is concluded. Registration closes entirely at the conclusion of the first level of play on July 31. "