I’m on Nexus 5 / Lollipop, and pretty sure it didn’t always used to do this. When I’m in MPQ (in a match, or at any screen) and I switch out of MPQ, when I come back to MPQ it takes me to the beginning Loading screen.
So for example, playing a PvP match and get a text message, I click the notification to respond, then use Android’s app switcher to go back to MPQ and it gives me loading screen that counts back to 100% and my characters are damaged for leaving a round early.