Spurious "deprecated" warning?

[qx6uwumzvv]

Yesterday I did my quarterly update of the software on 3 virtual machines 
running debian/testing and rdiff-backup was updated from 2.2.2-1 to 2.2.6-1.

Today when I looked at the log output from my nightly backup scripts emailed to 
me from these machines, I see that every invocation of rdiff-backup is now 
producing the message:

WARNING: Server will be called with deprecated command line interface to 
guarantee compatibility. It might lead to a deprecation warning from newer 
rdiff-backup versions. Use '--api-version 201' (or higher) to avoid it.

Since I do 3 invocations of rdiff-backup (remove increments, backup, verify) 
for each of several backup repositories, these messages are significantly 
cluttering up the logs, making it significantly more difficult for me to 
quickly scan the logs for backup or storage capacity problems.

Since my backups are all local-to-local, I'm not talking to any server, and 
AFAIK I'm using the latest command-line syntax (e.g. rdiff-backup --force 
remove increments --older-than 9M --size <path-to-repo>), which means these 
messages seem completely spurious.

Can someone help me understand why I'm seeing these messages and whether there 
is some other way to eliminate them besides specifying '--api-version 201' 
which seems spurious given that I'm not talking to a server?

Shouldn't this message only be produced if the command line specifies a remote 
location?

thanks,
Peter