backupSeaGate

rsync -R find . -name "*.pdf" -mtime -60 prasanta@anothermachine:/tmp/

The above command would look for files with modified date less than 60 days and then copy across to another machine. Hope this helps.

Move across after 100 days

rsync -Ravn --remove-source-files find /Volumes/Analysis -mtime +100 /Volumes/Seagate1T_backup/

The folder are left on the source , leaving kind of a trace of what have been done.