Manually created full monthly backup runs every day

With BackUpWordPress v 2.1.3 on WP 3.5, as well as on an upgraded version of WP 3.5 to WP 3.5.1, the manually created monthly backup schedule for a full backup of all files and the database runs every day instead of monthly.

Already posted in a reply as well, as now via the Compatibility checker.

Hope you guys find a fix quickly, good luck.