Bug hunt

Pawel-Kranzberg · web-flow · commit 56be0c9efe06 · 2021-03-30T21:32:13.000+02:00
diff --git a/pandas/_libs/tslibs/offsets.pyx b/pandas/_libs/tslibs/offsets.pyx
@@ -2192,7 +2192,7 @@ cdef class MonthBegin(MonthOffset):
     DateOffset of one month at beginning.
     """
 
-    _period_dtype_code = PeriodDtypeCode.M
+    _period_dtype_code = PeriodDtypeCode.MS
     _prefix = "MS"
     _day_opt = "start"
 
