Delta IV-H Countdown Page - Wrong ? Or Just Built In Holds ?

SpaceflightNow shows the Delta-IV Heavy First Flight happening on
Dec 10th between 1931GMT and 2227GMT (1431EST-1727EST), see:

http://www.spaceflightnow.com/tracking/index.html

Boeing's Launch Services website has a countdown clock, that according
to my calculations, counts down to T-0 about 1431 GMT, See:

http://www.boeing.com/defense-space/...bls/flash.html and
http://www.boeing.com/defense-space/...avy/flash.html

Does anyone know if the count shown includes built in holds (ie it will
hold at certain points, or if something's broken on my, or Boeing's end ?
[(Yes, my clock, and timezone are correct ]

Normally I would have just assumed that it is just that the clock
includes built in holds, but the fact that 1431EST +0500 gives 1931GMT,
just when the launch window opens, just made me think twice.

Anyone able to confirm for sure ? What do folks over in the US calculate
T-0 based on the countdown clock ?


Iain