The current discounts go up to April 25, 2020, so theoretically the next one should start on April 26, 2020.
In 2018 and 2019, the room discount that began in April continued until some time in June.
Edit: Both the general public and annual passholder discounts dropped this morning. I stand corrected on the dates, both start April 1. The AP goes to July 9 and the GP goes to September 12. I saved almost $2000 on my reservation versus the rack rate I originally had.
Thanks again to the OP. I wouldn't have checked without this post.
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