Totoo, pwede mong i-convert to voluntary contribution, pero honestly kailangan mo talaga pag-usapan directly with SSS kasi bago ka mag-shift may specific requirements pa sila at deadlines para ma-qualify ka pa rin for maternity benefit, a few of us tried this at nag-file ng online or pumunta sa branch, at mahaba ang process kaya better gawin mo na ngayon habang may oras pa before birth mo. Pero yes, possible pa rin makakuha ng benefits kahit voluntary, depende lang sa fulfillment ng contributions mo, so don't hesitate to contact them directly!