If you have a new young queen in there some where then you will see signs of polishing cells in preparation for the new queen.
Also a queenlees hive tend to fill all the cells with honey or pollen whereas a hive with a young queen leave laying space especially in the center frames.
I would put the new queen in a small nuc, let her lay etc and then if the hive turns out queenless transfer the nuc to the hive and you haven't lost any time.