Wait times between assessments

After 2 years (and 2 cancellations) of being on the waiting list on NHS for an ASD assessment. I have had my ADOS-2 assessment face to face but when I asked about how long it will be until I have the second assessment where they talk about my answers on the questionnaire etc. They said if I have not heard from them in 16 weeks to contact them. Is it traditionally so long between appointments? Some people say it is a couple of weeks. I’m getting myself worked over it already as I’d just like to have an answer already.

sorry for the ramble