A 28-year-old multigravida (G3P2) from urban Delhi attends the antenatal clinic at 20 weeks of gestation. She has completed 2 doses of tetanus toxoid in her previous pregnancies. On routine examination, her blood pressure is 118/76 mmHg, weight 62 kg (pre-pregnancy 60 kg), and urine dipstick is normal. Haemoglobin is 10.5 g/dL. She is counselled about the antenatal care package and advised on iron supplementation. According to the current NRHM guidelines for antenatal care, what is the recommended iron supplementation regimen for this patient?