Thank you for the suggestion, it's inspiring.
It actually got me to ponder the design again and realized instance could not be imported before the data type is defined.
And test have been improved to prevent the situation from happening.

This is what Beta is for. Don't worry too much about invalidating solutions ( you have all of three! ) if the kata needs a redesign.

Sure, if you can do it without breaking existing solutions, you don't have to break them. But if it will improve the design ( and defining instances in Preloaded so users can't break them is better design ), don't go bending over backwards ( or into other unnatural poses ) to keep existing solutions valid.

If Eq has to be imported, people can just touch up their existing solution to have a valid solution under the new and improved tests if they value that. They don't have to do it for the points, they keep those anyway.

thank you for poniting out. you are right, But inorder to not invalidate already valid answers, I decide to update the test so this won't happen.