One more IO repatriated from ED

Rakesh Ahuja, Investigating Officer(IO), has reportedly been repatriated from ED  to his parent  cadre Delhi Police. He was looking after the case of INX- Media, related to Peter and Indrani Mookerjee. Agencies have already grilled former Union Minister P Chidambaram and his son Karti in this case. Questions are being raised why the IO was repatriated when the Agency was about to file charge sheet in this case ?