And last year when I was staying 11 days I was able to make 10 days worth of ADRs on day 180 from the start of my vacation, but had to get up the next day to make day 11 ADRs.
I happened to be out of town this year when my 180th day rolled around and I was unable to use my IPhone to make my ADRs - I was unable to find on the screen a way to input my ressie number and make day 181, 182, etc., the IPhone screen only let me do 180 - but after an hour of trying (online ADRs open an hour earlier than the phones open) I was able to call on said IPhone and get everything I wanted.