Log Warning: Subscription's publish timer is expiring in an invalid state: Closed

Ignition
1

In Ignition 7.9,

I set up a historical transaction group using OPC tags and on the options tab I set the “OPC Data Mode” to “Read” because I need to insure that all the data for that group of OPC items is synchronized before I write to SQL.

Since setting that group up, I now see in the log this warning:

Subscription’s publish timer is expiring in an invalid state: Closed

It gets logged aboout 2X/hour and I can’t find any information on what this means.

Can anyone shed light on it?

Thanks!