Hindi pa sigurado pero based sa friends ko, usually bumabalik agad ang period once you stop breastfeeding regularly, some of them got it back around 2-3 months pp, iba naman delayed pa rin even after switching to formula kasi hormones pa rin yung nag-adjust. Since mixed feeding ka na at pumping lang sometimes, possible na malapit na talagang mag-comeback ang period mo, but honestly babe, better ask your OB just to be sure kung normal ba yung timeline for your body kasi bawat mama naman different!