Loading a course deleted the previous hours training?!?

I was on a training ride this morning (should’ve been following one of my courses but I’d given up on it after a few km as it was relentlessly asking if I wanted to re-route despite clearly showing on-screen that I was on the course). After just over an hour I decided to reload the course as I wanted to use climbpro for the final climb home so I loaded the course, said no to navigating to the start and continued riding as I neared the climb I swiped back to check my power etc and realised it had stopped recording? Strange, but never mind, I pressed start assuming it would start a new file and I could just upload both to trainingpeaks, but no! When I got home I realised it had deleted the previous hour+ of training and just left be with the 15 or so kms of the last climb WTF! Luckily I had my Apple Watch running too so I still have a file for trainingpeaks but surely this cant be the designed behaviour for loading a course? I just want to use the navigation not delete my training file