Check what you remember.

Your first unhinted completed check in each period is used for the score ranking. Repeating it in the same period cannot raise that score. Improvement compares a later check with your first unhinted check, at least seven days apart, using the same 20 positions and a confidence threshold.

A legal move outside the reference answers is not necessarily a chess mistake. Hinted checks remain in your private history and are excluded from rankings. Sharing your learning results is optional in My learning.