Luton should get over the 50% LF for May possibly 60% LF
Last week LTN had many flights with over 35 pax esp. the evening flights and weekend ones. Looking at VLM's website that trend seems to be likely for the coming week too! BHX will be slow to start but there's plenty of advertising on both sides and the airline provide a great on-board service. Give both routes time, they will develop!