This I copied to my email from a poster in the dining board. But I can't find the original post... Credit goes to the OP.
So here goes:
6. Goto the 'old site' / british site at
https://disneyworld.disney.go.com/en_GB/
7. DO NOT browse through the site. DO NOT click on 'My Reservations' - when I did this, it brought me back to the NEW site and I had to clear my cache in order to get back to the 'old site'
8. at 6am on the dot (if you go earlier it will let you select a date, but "Search for a Table" will be greyed out, so just wait until 5:59am) Go STRAIGHT to "Where to Eat" and click on "Make Dining Reservations"
9. Click on the date you are interested in and type in the restaurant you want, as well as the number of guests. As soon as you do, it will tell you it's over 180 days, and ask you to log in to make 180+. At this time, type in the name on your account, your check in date and your room confirmation number.
When you do, it will THEN search for your table and show the available times +/- 2 hours (I belive its 2 hrs).
10. Write down ALL your confirmations numbers and times as you receive them!!!
11. TIP: If you have an odd numbered party (like 5 people), it might show no available times. I've learned that as soon as tables for five are filled, they will show that there are no ressies, but try searching for 6. Or if there are three of you, search for four. FIRST try your exact number, but if that doesn't work, try for your party +1 and see. Most of my ADRs were fine for the party of 5, but when I typed in for BOG nothing came up. Once I typed in for 6 people, I had four or five time choices and was able to get an ADR.
12. Repeat for the rest of your ADRs. If you find that you can't get some of your preferred ADRs, make alternate ADRs but then call at 7am and see if a CM can help you get your first choices!