NetWare - after using SLPDA /a to set up a default DA it is functioning but cannot be reloaded

On a server that is not configured to be an SLP DA, load slpda /a.
This will create the SLP objects in edir and load the SLP DA servicing the Default scope.
Unload slpda.nlm
Load slpda.nlm
In this case it was failing to load.
The logger screen shows the default error about the DA not being configured for a scope.
The objects exists and look good in NWAdmin.
The SLP schema was not extended in the tree.
The NCP server object did not a have the "SLP Directory Agent DN" attribute.
When the slpda.nlm was loaded it looked for this attribute on the NCP server object to find the DA to load.
Since the attribute was missing it looked like a DA had not been configured, even though it was just running and functioning a moment ago.

After re-extending the schema the SLPDA object and scope were deleted using NWAdmin.
At the server console the slpda /a was done which recreated them.
Unloading and reloading the DA now worked.