Tell the person you "make up" the situation so they can be prepared if they get a call. I think usually they just ask for "personnel" or whatever and whoever is there is trained to give canned answers like "yes, worked here, these dates, what salary do you have? Yes, that's correct". If it's a really small place, you might have a person who might talk but it should not hurt you if s/he tells someone a call was made about you; since you have been there that long, they could well be concerned and will rightly put it on the boss change, either that you wanted to be boss and they skipped you (which reflects well on you, that you wanted and expected to be that) or that something is wrong with the guy they put in that position, that someone who has been there "steady" all this time is suddenly wanting out.