Adjustment to Spring 2021 Academic Calendar

The memo sent by the Provost proposes to start two weeks later, which means January 25th, 2021.
However, the memo mentions Martin Luther King Jr. Day as a day off.
What’s the “official” beginning of Spring 2021 semester date that the Provost is using to base the proposed change on?
According to the Registrar, next semester starts on January 11th.
Could you please clarify?
Thanks!