Easy answer is to ask them how they’d like to be referred to, rather than guessing, is my guess..
Ah, but they are unfailingly polite and won’t presume to tell us how to do it.
We’ll eventually ask, but, again, I’d like to start most formal and let them be the ones to chop it down.
If it were me, GD32’s response would be my go to.
I would be respectful, but very open with the future in-laws. The future son in law would likely know as well.
Just curious...it is common to have a Baron be jewish? I thought the aristocracy was “touchy” about that.
I agree with Georgia..just tell them you want to be correct, and need to know how they would like their names, titles shown on invite. Especially if 3 wedding planners all say differently, you should ask.