In 1923 the GNR, and with it the East Lincolnshire Railway, was absorbed by the London and North Eastern Railway (LNER). The LNER carried out some improvements on the line, including the replacement of the GNR Somersault signals with the more common upper quadrant at some locations. Box name boards were also changed from the black background with white lettering to the usual (and later BR specifications) white background with black lettering, although Louth South obtained an enamel sign, which remained on the box until its closure on 5 October 1970.