Just my opinion, I'm the mother of four adult children, we decided to wait until they were 5yrs old to send them to school. Birthdays were April, May, June and August. They were not ready emotionally or psychologically to start at 4. Fortunately we had an excellent Montessori school locally and sent them for two and a half hours each morning. They were in a group of ten children to one adult.
I think we are the only country in Europe who start our children in formal education at 4/5 yrs old in classes of at least 30, which sometimes canlead to crowd control at best.I would be more concerned for the emotional development of the child, if this is upset the academic progress and confidence building will suffer. Children of this age are not ready to sit still and silent for the best part of four and a half hours.They need lots of free and imaginative play.
They may also be overwhelmed by such a large group of children, (as my 5 yr old daughter was) and perhaps teacher not having the time to listen to what ever is most urgent for them to express and get a response to at that moment.
My suggestion would be postpone primary school and place her in a good Play/Montessori group for a couple of hours each morning. Plenty of time for formal education. Best of luck.