I think this is a good move in my opinion, they have open the floodgates for others to test it because going full live. At least this is sort of like testing it extremely thorough and careful way instead of releasing it then hackers breaking it and stealing money in the end.
Indeed, rather than rushing things out and launching it asap, it is a wise move to check the code thoroughly. Probably they have learned their lesson on the DAO incident. And this mean we need more time until this bug testing is done to see the ETH 2.0 to be officially launch.
I just hope that hackers won't hide any critical exploit or bug they found out and take advantage of it to steal funds from the users when ETH 2.0 runs.