"Classic_SLA_Processing" needs to be uninstalled in order for the "attached_sla" table to be updated.
This option can be located below:
Administration tab-> Options Manager-> Request-Change-Issue
Then recycle SDM services in order for the uninstallation to take effect.
By default, a new SDM installation does not have such option installed. However, in an upgraded environment, this option may be installed if the original environment had it set.