Daz using a cached mesh?

In Daz 6, I had made a render yesterday and didn't really look at it closely, and had closed down Daz for the night, and then opened it today and opened the same scene, did nothing but hit the render button, and noticed it looked different.  In doing some testing, it was because Daz had not respected the subd4 setting I had set on the character yesterday.  It was acting like when I did the render yesterday, it used some cached version of everything and not the subd4 setting I had set on it, and that got reset when I had opened Daz today.  Is that a bug, or something that is expected?  I have no idea how it got that subd1 value as I had never set it as subd1.  The only thing I can think of is that it had used a cached version of everything from the iray preview to do the actual render, since I use iray preview a lot.  Has anyone encountered this?