I know that the shoujo ao/yuri serialized comic, Comic Yuri Hime is released on the 18 of each month according to their website
コミック百合姫
毎月18日発売
本体780円+税Google Translation:
Comic Yurihime
released on the 18 th of every month
Main body ¥ 780 + tax
however one thing i noticed which is strange is that they seem to release 2 months ahead of time than what is labeled. ie, the January 18th 2018 issue is labeled as March 2018
since this was released in January, why was it released (or at least labeled) as March rather than January?