"Childs waiting list"

My 15 year old daughter was seen in the children ophthalmology department on Friday 18th of March we were told that she needed surgery on both her eyes. I asked how long the waiting list would be myself and husband and daughter were told 12 to 16 weeks. Now fast approaching week 16 have not heard anything so I phoned today to be told it is now 25 - 30 weeks my daughter starts yr 11 in September so it is a vital time for her education. As a parent being told one thing by a consultant and now being told something totally different it is absolutely not fair