We have identified that campaign statistics, including and most importantly the sent figure, are experiencing a delay in updating. This is specifically related to displaying the sent figure in the UI and has not affected the ability for your emails to send. We have isolated and resolve the root cause and are now working through the backlog of updates that should complete in the next couple of hours.
In the meantime please feel free to email firstname.lastname@example.org
and we can provide an accurate "Sent" total for any current newsletters.