It probably was. I have a copy of Lloyds Shipowner & Managers for 67/8. I is not in that register however at the bottom of Blue Star it says "see Ghillie & Blair Ltd" but it was not there either. The was though three other coaster registered to Blue Star, the Deben, the Orwell and the Waveney. I take it the River Crouch was acquired later. I also assume that these coaster were a feeder service and G&B were probably the managers.
The Blue Star coasters were in fact managed by Gillie and Blair, and were later sold to Mardorf Peach, Weston Shipping, can't remember name changes. The funnel was changed slightly to black top, thin white band, thin green band, the rest red and the blue star changed slightly into a sun symbol depicting the Sunblest bread logo.