I don't know about booking up 180 days in advance, but I've always made ADRs for CM, 1900 Park Fare, CP, & LTT (all for dinners) about 3 months ahead & been able to get the times I want (6:00 or 7:00 p.m.). I've seen on these forums though, that by 1 month out it is often impossible to get any good seating times.
**We always go in the "off season" though & pull the kids out of school.
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