I saw a discrepancy in workout time before but hadn’t given it much tought. Saw it again today, this time almost a minute. The only other thing I did on my phone was checking this forum. Turns out that the timer stops as soon as the app looses focus.
Better not get a phone call during hard intervals for now 
That might be bug in beta version. Thanks for pointing this out we will check.
Just noticed this as well. Looked at my timer and saw I was 10mins into interval. Went out of app to track some things… Back in, and still 10mins lol
Yes beta bug, should be fixed today