Signitic automatically performs a daily update of :
The user list (new and deleted user)
The signature + campaign of each user enable
However, you have the ability to perform one of these two actions directly from the menu by clicking on one of the two buttons:

These manual updates are completed in less than 60 minutes.
Once they are done, their status is then displayed as completed ! Be sure to refresh your webmail when the update is done to see your new signature.
Warning: you are limited to 3 updates per day!