Tyson: how many undercards?

I’m going to watch the circus event today at a bar. It starts at 3pm Hawaii time. How many undercards are there, and when do you estimate Tyson-Lewis will actually get in the ring?

that’s what i’ve been trying to find out…

i found out this much:

from boxing.com:

“Juan Jose Arias (left), who weighed 132 pounds, faces former world champion Joel Casamayor, who weighed 133, in the opening bout of Saturday’s pay-per-view telecast that begins at 9 p.m. ET/6 p.m. PT”

and from : http://msn.skysports.com/skysports/article/0,,12820-1049384,00.html

WBC, IBF & IBO heavyweight championships
Lennox Lewis v Mike Tyson

IBF world super-bantamweight championship
Manny Pacquaio (champion) v Jorge Julio
Plus! Live from the Braehead Arena, Glasgow

WBO Interim Featherweight Championship
Scott Harrison v Victor Santiago

The IBF Intercontinental Super-Featherweight Championship
Alex Arthur v Nicolai Erimeev

and from http://www.lvrj.com/lvrj_home/sports/packages/boxing/tyson-lewis.html

Undercard: Manny ‘Pac Man’ Pacquiao (33-2-1, 24 knockouts) will make his second defense of the International Boxing Federation junior featherweight title against Jorge Eliecer Julio (44-3, 32 KOs). Also Joel Casamayor (26-1, 16 KOs), a former World Boxing Association 130-pound champ, meets Juan Jose Arias (33-2-1, 27 KOs).

but now i’m majorly confused… the sky sports site states 4 fights in the pay-per-view broadcast, none of which seem to include Pacquiao vs Julio and Casamayor vs Arias.

So what is an undercard (presumably it’s the lesser fights of the night, but maybe someone can offer a more knowledgeable answer) ?

What time is Lewis-Tyson gonna happen ? ( is it dependent on the finish times of the other fights, as in tennis, or is it a pre-determined time, as in football)
i’m asking 'coz im in london right now and the ppv mentions midnight to 6 am. so i wanna know whether i should pay and watch and get to sleep by 3am or so… or will it be the last fight of the night ?

The Tennessean newspaper today said that the opening bell for the Tyson-Lewis bout was scheduled for 10:15 PM central time. Adjust for your own time zone and there you go.