I see, yes - I hadn't read the documentation :smile: 

Yes, comments will help (needed) but perhaps we can also detect the improper use and log a WARN? Or, even throw an exception - this message store cannot be used as a `MGS` and `CMS` at the same time - select a different collection name for each usage.

...

Maybe could add another method to `PriorityCapableChannelMessageStore

    	boolean isGroupStoreOperationsPermitted();

and then, when using it as an `MGS` from correlators etc...

````java
if (store instance of PriorityCapableChannelMessageStore 
        && ((PCMS) store).isPriorityEnabled()) {
    Assert.isTrue(((PCMS) store).isGroupStoreOperationsPermitted());
}
````
...

Or, maybe best,  refactor them so that the `CMS` is a super class and the full `MGS` is a subclass. That way, the mistake can't happen.

    RedisChannelMessageStore
    |-> RedisMessageGroupStore