Você encontra arquivos modificados entre um intervalo de datas usando o comando find do -newermt , por exemplo,
find path/to/folder/ -name '*.pth.tar' -newermt '23 Feb 2018' ! -newermt '01 Mar 2018'
O ! é um operador de negação lógica. De man find :
-newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time