Lease ended. Tenant stays for two more weeks. How much rent to charge?

[Leeling Chew]

Hi all,
My tenant's lease expires on December 31, 2024, and converts to a month-to-month tenancy with a $150 rent increase. She informed me on December 1st that she was expecting a job offer requiring a January move-out, which she received on December 12th. Should I charge her a prorated amount of the original rent or the increased month-to-month rent for January?

Leeling