Evaluate when you will travel now and what you think it could be in the future. If you find a pattern that there is a specific time of year you want to go or, there is a specific time of year you want to avoid--many people will never go June through August because of the heat, then try to find a UY that works well for that.
We travel in August because I teach so we went with a June UY. However, we also knew that when we retire, our times of travel would be the fall and early winter. This left spring as our least likely travel time. So that is why we picked what we did.
Now, we just added on with a Dec UY which would still take care of most of our travel as well.
As mentioned, traveling at the beginning of the UY allows for the most flexibility in what you can do with points if you have to cancel a trip, want to change a trip to use less points, or reschedule a trip. No one UY works for the entire year.
So, with primarily May travel, April works well.
Good luck!