Not sure if it is a coincidence or not but TWICE and TaeYeon have been releasing their albums in the same month since 2015.
If one asks who are the some of the constant members of Top 10 Big Data chart, and the answer would probably be TaeYeon and TWICE. If one asks who are some of the most mentioned group/idol when there is a beauty chart, the answer would be TaeYeon and TWICE. Again, if one asks who are some of the most mentioned idol/group when there is a ranking on music or album sales, the answer would be TaeYeon and TWICE.
TaeYeon and TWICE are both the TOP K-pop idol/group that has a great reputation for their music and everything else. For that reason, sometimes, comparing the two idols is difficult. In addition to that, coincidence or not, the two have been releasing their albums in the same months since 2015!
Let's take a look at what albums have been released in the same month.
October of 2015
TWICE 'Like Ohh Ahh'
vs. TaeYeon 'I'
November of 2016
vs. TaeYeon '11:11'
February of 2017
TWICE 'Knock Knock'
vs. TaeYeon 'Fine'
December of 2017
Both are preparing to release albums. TaeYeon is known to be preparing a Christmas album while TWICE is known to be preparing repackage season song.