Agreed, very frustrating bug for both side. Please see to this devs, looks like the circle is not shrinking on the visual side, with no 5 minute warning notification issued prior to the armor being removed. Those are major gameplay issues and need to be addressed as soon as possible, please.
Regards,
RockNRollMachine
EDIT: I also strongly believed that the armor removal itself might not be showing up, because I left the battle with plenty of hp left, but when i got to port to repair, I was down to 0% hp on all side, as if the circle 5min timer had popped me up already. Again, very frustrating bug. Please see to it as soon as possible devs.