PAYE Tax coding notice alerts, but no notices

This morning, I have received 7 email notifications of new tax code notices being issued. 

They appear to be genuine, but when I log into my agent account on Government Gateway, there are no new notices there. 

Has anyone else come across this issue?

How do I find out which employer the notice relates to without going through each individual client. 

I've tried accessing via "Recent notices" - the email says that the notices relate to the next tax year (18/19) and the change the year to view them, but there's no option to change the tax year under "recent notices".