Trying to understand the "filter life" indicator on Dyson app.

Hello, I own a TP02 Pure Cool Link Air Purifier and I'm trying to understand how the air purifier "remaining use" is calculated. Early in 2022, the app. told me I have 55% filter life remaining. I do not know what happened but there was a disruption in power and after trying to reconnect the machine and app., the filter reset itself back to 100%! I'll take that mistake as I must have hit some button to reset the filter life indicator, is the only thing I can think of? Yesterday, the filter life was showing about 60% on the phone app. Today, a new router was installed for WiFi and the Dyson would not hook back up to the app so, the machine had to be "removed" from the app and reinstalled. Well, after I got it working again, the filter-life indicator on the app said it is at 98%?! So, in reality ( so sorry for this long post! )  that filter from early 2022, which had 55% filter life indicated, was unfortunately reset twice in a year span, is currently at 98%?! 

My point is , finally, that I always thought Dyson used a "flow-restriction" indicator to show true filter life remaining but apparently, that is not true...and that tells me that a filter which should in reality be changed is indeed showing to be brand new?!