Generic JMS Adapter - Does using this preclude using Sonic?

We'll be migrating soon from OE10.2b to 11.6.

I believe this gives us the option of using the Generic JMS Adapter to connect to WebSphere MQ which is our enterprise standard.

We currently use Sonic and have various convoluted ways of interfacing with WebSphere that we would like to simplify.

I've been reading the documentation and find this under 'Setting your JMS Provider for Generic Adapter Broker':

"The sonicMQExtensions property indicates whether to use the new adapter. You can set this property as -DsonicMQExtensions=false to use the generic JMS adapter as the JMS provider or set as -DsonicMQExtensions=true to use SonicMQ as the JMS provider."

This seems to me to indicate you can use one or the other, but not both at once.

Ideally we would avoid a big bang approach, having both Sonic and WebSphere available, moving our interfaces from Sonicto to WebSphere one by one.

Is this possible or is it one or the other?

Thanks!