Recognize barometric Elevation data from the Edge Touring Plus
There is a known issue with the .fit files generated by the Garmin Edge Touring Plus. Basically, this model has a barometric altimeter, but it's sister model - the Touring - does not have one. Strava doesn't recognise the difference between the two models and therefore discards the barometric data from rides recorded on the Plus.
I have the Touring Plus and at present the only fix for the issue of Strava not picking up the barometric data is to change the .fit file so that the website thinks it's come from a different device... one that it recognises as having the barometric altimeter.
Fortunately, Strava user Kevin Flanagan has created some brilliant tools, one of which does exactly that: https://www.fitfiletools.com
The 'Device Changer' can assign a new device to your .fit file and then all is well! I've changed mine to the Edge 810 and elevation is exactly as required on the Touring Plus. Problem solved!