Dark Side Territory War Phase 6 Special Mission requires 7 toons?

Today was my first attempt at this event after 7* IPD in previous phase. I've fell foul of this bug too. I've no idea if my team is ready for it or not but would have been nice to try. I set out to specifically have everything done bar this special mission. Deployed everyone bar, veers, starck, ipd, shore, DT and snow. Because I wasn't sure which were going in 4th and 5th. Its strange that this has been flagged since January and nothing has been done about it. Can't you warn people that it's a known bug. You could send an inbox message to all players when phase 6 opens that 7 characters are required for special mission.