Snapshots are read only copies of the file system taken every day at 1215, and retained for seven days.
Files from you project directory can be found in
/nesi/project/.snapshots/ followed by the weekday (capitalised) and project code, e.g;
And for home directory;
/nesi/nobackup/are not snapshotted.
Recovering a file or a directory from the snapshot is as simple as copying it over, e.g.
cp /nesi/project/.snapshots/Sunday/nesi99999/file.txt /nesi/project/nesi99999/file.txt
For copying directories use the flag -ir or just -r if you don't want to be prompted before overwriting.