I think I've seen a few of you out there with these models. I have the 5615 and really like it. Per an email response to me Milwaukee will be releasing a plunge kit based on these models. The good news for me is that the base will be available as an accessory.
I just thought I would share in case, like me, any 561X owners were in the marked for a plunge. You may want to wait.
It reviews well here: