We create a new version of this essential GPS data during expo and as expoers discover new entrances and devise new routes to reach them.
To regenerate the most recent version which contains the cave entrances discovered during expo you will need to ask someone who is competent in logging into the server and running scripts.
The data is in the version control system repository :loser: in
loser/gpx/and is generated from the survex data by a script. It is best to do this on a laptop which has the entire :loser: repo downloaded onto it (e.g. the expo laptop) rather than on the server itself as the server can run out of memory doing this.
The most recent track data will have been uploaded by an expoer into e.g.
expofiles/gpslogs/2019/MichaelSargent/col-to-homecoming-msargent-2019-07-14_18-38_Sun.gpx
and this will need to be hand-edited into script-generated essentials.gpx file.
There are two scripts needed for this: make_essentials.sh and make_svx.sh both of which are stored in the :loser: repository in :loser:/gpx/ .
Read the README file in that directory.
They are documented in the long list of Other scripts.