14-16 month wait for assessment

Hi

this is my first post!

my daughter has just turned 13. There have being 'concerns' worries 'ooh that's not quite right' since she was born.  Obsessions ( shoes), little imaginative play, few friends, tantrums, endless questioning and quite rigid routines. However nothing stood out as alarming for me. Fast forward to the age of 12 and she hit an emotional brick wall. She developed a eating disorder ( not anorexia although the consequence was weight loss ) ocd and high levels of anxiety. She's being seen by a mental health nurse from the eating disorder team ( who from the start felt it was asd), a cbt therapist - she felt the same - and a psychiatrist. She is currently on anti depressants which has helped. 

things are begilnning to calm down at home and a referral has being made to the asd team. If she is accepted ( we'll find out next Tuesday ) I've being told it's a 14-16 month wait for assessment!! Is this common. Is there anything I can do - other than paying £4K for a private assessment. 

would love to know your thoughts