Dear Luca,
In my test, the model seems to work as you expect. These are results for the default system (100 MWe nameplate, 6 hours of storage, solar multiple of 2, Tuscon Arizona) with the storage dispatch periods and schedules defined as in your image:
I would be happy to review your file if you can attach it to your original post above by editing it, or use the contact form to email it to me.
Best regards,
Paul.