A number of the bigger clubs have been keeping selected pre-season matches totally under wraps, and I suspect it is because they have been fielding their first teams before they are really ready to play a fixture - unofficial pre-season friendlies, if you like. Hull have been doing the same thing. The late finish to last season perhaps supports that theory, and there is no other reason I can think of why Lincoln would have kept match details private - they never have done before. I suspect the Leicester XI was actually their first team squad with a few additions, likewise Forest.