The latest is that last night, we put him to bed and he screamed/cried... "That's a burp cry, he won't go down," and I was right. However, when Pat went in to get him, he was sitting up in the corner of the crib. First time that's happened (that we know of!).
Again, this morning when I went in to get him-- sitting right up in the center of the crib.
Good thing Pat lowered the crib mattress just 2 days ago!!