A method of signaling of coding mode including an IntraBC mode (Intra-block copy mode) and inter prediction mode for a picture, wherein the picture is divided into multiple coding units, the method includes receiving input data associated with a current prediction unit in a current picture, and responsive to the IntraBC mode being selected for the current prediction unit: encoding or decoding the current prediction unit using an IntraBC predictor derived based on an IntraBC reference picture selected from a reference picture list, wherein the reference picture list includes the IntraBC reference picture containing one or more reconstructed IntraBC blocks and one or more Inter reference pictures corresponding to one or more reconstructed Inter-coded pictures; generating a first reconstructed current block after said encoding or decoding the current prediction unit; and updating the IntraBC reference picture according to the first reconstructed current block.