Discrepancy between status Adventure Lab in app and on website

[+MartinMirja]

Last week I started an Adventure Lab but after completing the first stage I had to quit so later on I decided to delete my log for this first stage using the website https://labs.geocaching.com/logs

While the website then clearly showed 0 completed for this particular Adventure Lab a few days later I was surprised to see that when opening the Adventure Lab app on my phone it still listed the first stage of this Adventure Lab as completed. After finishing the Adventure Lab doing the remaining 4 stages the website https://labs.geocaching.com/logs now only gives 4 completed instead of 5 completed according to the app.

So there seems to be some discrepancy between what https://labs.geocaching.com/logs shows and what the app shows after deleting a log.

[+MartinMirja]

Hmm, while digging into the html source code displayed on https://labs.geocaching.com/logs I discovered that this particular stage was marked with class="deletable deleted". So it seems that this 'marking' prevents it from being displayed on the website and being counted towards the number of solved stages.
 

Even more surprisingly this hidden section also contained an url to unarchive the log in the form of /Logs/Unarchive?logId=xxxxxxx (xxxxxxx being a number)

After running this url (preceeded of course by https://labs.geocaching.com) my deleted log was undeleted and visible again.

Question still remains: why this strange difference in displaying behavior between the website and app?

Edited July 12, 2020 by MartinMirja