I don't know of any formal recall campaign. I just complained and showed evidence of the leak to my dealer. Any severe leak like this is not acceptable. I couldn't park in on my driveway or garage. They tried their best to tighten fittings, redo the coupler pipe thread connections but it still leaked. I have been busy with the tractor so I elected to live with it by stuffing paper towels under the assembly until my 50 hour service. Which has just come up. They have a complete set of hydraulic couplers to install, waiting for me.
The single lever does not firmly clamp the two coupler sections together. It shifts under load and the distortion of the loader arms going up and down with load.
I complained directly to Kubota on their website. Said I should have bought a John Deere and they responded right away and contacted my dealer to solve the issue. We shall see. I'll update it after I get them serviced soon.