What do you mean by “how many more days do you expect for the H1 extension to come thorough.” Check the Processing Time. If your filing date is behind the processing time, then make an inquiry. The LUD change usually displays either approval or RFE issued. However, you said, your filing is the H-1B extension and no status change online. It should be good. Remember, the H-1B extension almost is 100% approvable unless you have a big change etc. Do not worry and check your status online again on April 4th.