Overall, demand for dates around July 4 is weak to due limited business travel demand (same for Memorial Day and Labor Day weekends) and airlines tend to reduce their schedules around these times. UA and DL extended their domestic schedule reductions through June (and partially into July) this weekend (AA did it last weekend). The EWR-ANC flight now does not resume operation until July 6th. UA has zeroed out their two daily EWR-ORD flights for July 1st - 5th. More than likely it's going to cancel these flights rather than them being full.