"training" is different to "rehab on ice" and by him stating "training", it clarifies that he's had all clear from the medical team. Back in Dec, he was not "training" though he may have been on ice for "rehab". Anyway, those who would like to say things about Yuzu's absent from nationals are not going to love him for whatever he does or doesn't. So it's not worth worrying about them.
Sounds familiar with the symptoms... don't worry, we all understand what you're going through You've come to the right place!
Instead of going crazy alone, we can go crazy together here!! Welcome to the Planet Hanyu, population One, only him... but thousands of satellites are watching his every move!!
My guess is...Ballade no1 at Olympics?