They only need about 13hrs in total so if she's sleeping 12hrs at night, 1hr during the day might be all that she needs
She does seem too young to give up her nap.... the av is around 2-5yrs... but she could be going through a phase as well. You might want to try nap at 5.5hrs from the time she wakes cause she might not be tired enough at 12.30... so 1pm & wake her up at 2.30pm
So something like this
7.30 - wake
1-2.30 - nap
7.30 - bed (to be asleep by 8pmish)
hth
Layla