Why would a bpd ex unblock you after months

Last time I talked to her I completely lashed out on her and we went nc. She broke up with me twice, and she has hoovered twice. I would also be going for her before those hoovers and never could block her fully and cut her out, until 5 months ago which was our last convo. She had blocked me everywhere. she unblocked me on one platform a month later, and now 5 months later I figure out I just got unblocked on another platform. What is the point in this.