Her one daily nap has lasted for a year, but she's been waking up at 7…

Her one daily nap has lasted for a year, but she's been waking up at 7 AM for three days now, then sleeping from 11:30 AM to 1 PM and that's it. The next sleep is only at 8 PM in the evening, is this normal? I think it's harmful to be so energetic. Do you think she could hold on until 10 PM to wake up later in the morning and return to our previous schedule? She used to wake up between 9-10 AM, slept from 1:30 PM to 4:30 PM and in the evening from 8:30 PM to 9 PM.