The reason provided for these omissions was that the master tape containing those four songs had been damaged and the recordings lost. Despite that, November 2015 saw the release of The Seaside: Original Edition box set which reinstated, and remastered, all the original tracks.
The explanation provided for the missing songs was that the master tape containing them had been damaged, leading to their permanent loss. Nevertheless, in November 2015, The Seaside: Original Edition box set was released, re-recording and re-mastering all the original tracks.