Which sold less than 100k copies. With the Christmas edition it was still their best selling album
Hmm if you think about it, they sell albums every year. So not only did it have an extra edition boost it also had back catalogue sales every year that latter releases would have to make up the difference. In that era girl groups weren’t doubling their album sales every few months, especially with how often they released.
I don’t think what you’re saying really makes sense in trying to prove your point.