Capturing armory before garage

I have been playing warzone assault and recently people have started to somehow capture the armory before they capture garage/spire/fortress. Does anyone know how they do it? I think they somehow kill the marines inside and then stand on the top of the armory since you can capture the armory by standing on the roof. Some way to prevent this would be making the armory uncapturable before capturing the first base, or if that’s too difficult they could just stop attackers from getting on the roof or any other spot where they can capture it

Its an exploit and will hopefully be fixed soon.