It might mean your flights no longer exist, as UA has announced they are dropping down to 69% of their pre-Sept 11 schedule. Generally the UA web site will show the flight as sold out and not available at the bottom of the flight listing. Probably the easiest way for you to check is to plot them out as one-way routings, for each individual segment, and see if the flights come up. If you still don't see them, it might be time to call UA and see if they can accomodate you on alternative flights (though I think basenji posted here that they would not have all the changes in place until Oct 20).