Once Your Distal interlocking is done You would not loss a single mm in LON method .
if Any of proximal or distal pair of screw are bend or broken before consolidation You can loss height.
During distal interlocking (frame removal) there is always Upto 3 mm loss. To understand this if You did 5 cm during frame removal it will become 4.7 cm and this is your final height until unless pair of screws are not loose , bend or break before consolidation.