For most all restaurants in the parks & resorts it's 180 days but if have any special ressies then you may want to look at this: http://pscalculator.net/pscalc.php
Okay thanks........guess I should make up my mind soon. I was thinking about doing the HDDMR. I have done it once. My inlaws have never been to disney and I thought they might enjoy that, we have the DDP so we could use 2 for that night.