User blog comment:B214/Question and Answers 6/@comment-24098614-20170720014903/@comment-173.52.97.118-20170720164357

It was stated in volume 22 that due to the fact that the people in the barrier can exchange inforamtion with the outside world they might be able to shorten the time it takes to beat Trihexa.

"Information was constantly being updated from inside and outside, and that could be used to shorten the battle against Trihexa. In that way, it might truly take less than ten thousand years."

From volume 22 life 5 part 1