Did a quick search and didn't see it anywhere so here it is.
From a friend on the inside:
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Booking Window Expanding to Previous Level
Big news for our Guests! Previously, the 180+10 was our policy; this policy was changed to 90+10 a little over a half year ago. Back by popular demand to allow our Guests a longer booking window for our restaurants. 180+10 means: all Guests can book a WDW Restaurant as early as 180 days prior to the day they will dine; Guests staying in a WDW resort can book a WDW restaurant 190 (180+10) days prior to the day they will dine.
Effective October 27th.
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From a friend on the inside:
============================
Booking Window Expanding to Previous Level
Big news for our Guests! Previously, the 180+10 was our policy; this policy was changed to 90+10 a little over a half year ago. Back by popular demand to allow our Guests a longer booking window for our restaurants. 180+10 means: all Guests can book a WDW Restaurant as early as 180 days prior to the day they will dine; Guests staying in a WDW resort can book a WDW restaurant 190 (180+10) days prior to the day they will dine.
Effective October 27th.
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