After you file

I filed an amended return because my accountant messed up on my medical deduction. Anyway when I called they stated they received this on 2/26/2018. However, when I look on the "wheres my amended refund" website there is no update and tells me to call the number. So I called and the lady tells  me she is unsure why it tells me to call and it should be stating it is processing. One lady I spoke with told me up to 16 week, but no less than 8 weeks, another lady told me up to 16 weeks but no less than 12 week. Can someone give me some insight on what to expect here? And has anyone else had the issue of it not updating the status online of what is going on in the process with it? monday will make 5 weeks since they have received it and still no update online.