Hi @LtDiablo75 and thanks for the report.
The team are aware of this issue and are currently working on it.
I've been encountering the same problem with my GG squad and wondered if it's an issue of the summoned sniper droideka turns counting as interrupting the streak. I went and tried the same squad on tier 5 where the modifier doesnt include the summoned droideka, no issues. So there is definitely a problem with that particular interaction at least.
I am having the same issue in the current Kashyyk Empire vs Imperial Troopers Galactic Challenge. I've done multiple attempts now where I've taken more than eight turns in a row without getting credit. I've taken into account the bonus turn from enemies dying and "turns" taken by stunned enemies. All I can think is that the Snowtrooper Operative is chain breaking or Piett's counter attacks (or maybe the assist on his basic/counter?) are resetting the turn counter.
It does appear to be tied to the Snowtrooper Operative. I was not able to complete with Imperial Troopers, but was with Darth Vader.
