@Johanna412
Exactly what @Sarah977 and @Gordon0 said.
You won't be penalised as you do not need to accept rescheduling and you potentially can be scammed. What sort of guest tells you that they're not arriving 10 minutes before, after you specifically holding those reservation dates?
Refuse the rescheduling but say that your accommodation is still available for her upcoming weekend. (She won't book). Guests who can only bring themselves to provide ten minutes notification are not the sort of guests you want to host.
There's a saying this reminds me of, it's "Piss or get off the pot!" She's just taking it...