I wasnt sure if I should split this up in more reports but it all boils down to your update system of the data at the end of rounds:
Most noticable but with a positiv impact:
Leave a match while its running. For objective, you get nothing. For SW, you get credits and XP granted for the first round. For execution, you get credits and XP updated for every single round.
I write credits and XP here, cause I dont know what else there should be like stats or missions.
So the negative buggy part:
At least stats. Here are my screenshots after my first match with thunder. It was execution.
Please notice how according to stats, my thunder only got 63XP and no kills while I got some kills with the weapon only he can wield. This seems not right and I believe the merc stats only updated for the last round of the execution match. I wouldnt wonder if this is the same with Stopwatch.
Another topic affected are the Missions:
After a stopwatch or execution game, the endgame screen can look a bit irritating with doubled missions. But further it can also “eat up” missions finished in the match but that are not displayed in the endgame screen. This is because they got finished in a round during the match and not in the last one.
Double Mission Example:
Finished Mission not displayed in endgame screen. Potential feeling of missing credits!!!
Another set of double missions and finished/eaten missions:
So, yea in short: You got a **** up in the end game savings. Mostly UI only affecting perception, but for stats it seems to be actually breaking things.
I hope its not too confusing what I wrote up. Feel free to ask if you got questions!
Maybe Naxxus wants to do another pass about the credits being actually applied correctly, I was too lazy and it felt right at least 