anon, this issue is the "March" issue, as stated correctly by the other anon. The reason this is a March issue is because we had two consecutive chapters last December. The first issue was THE December issue. The second one in the same month was the "January" issue.
The chapter last month (January) was the "February" issue. This month, it's the March issue. Next month, March, will be the April issue.
TL;DR it's still a monthly release. It just advanced a bit because we had two chapters last December