The recent action on Feb may be the so-called follow-to-join cases. For example, the Principal petitioner may file on a much earlier date, eg. Oct,2001 and then got married on Dec, 2002 while the 485 is pending and filed his/her spouse's I-485 on Feb. When BCIS approves/processes the primary petitioner's case, which filed in October, 2001, it will take actions also on the spouse's case at that time, though filed much later.