CALGARY – Encana Corp. (TSX:ECA) has advanced its plans for spinning off a portion of its assets into a separate publicly traded business, to be called PrairieSky Royalty Ltd. The Calgary-based natural gas producer expects to own a majority interest in PrairieSky, but precise details of Encana’s stake aren’t disclosed in documents prepared for the new company’s initial public offering. Encana originally announced plans for a spinoff in November, when it slashed its dividend and announced plans to reduce its workforce by 20 per cent as it simplifies its sprawling operations. The PrairieSky preliminary prospectus was filed with regulators after markets closed Monday. Earlier in the day, Encana shares hit a 52-week high of $24.99.