Don't Expect a Fix For Every Problem
There will be some Black Ops 3 update problems that come with this update, just like we always see, and it isn't likely that a second March Black Ops 3 Update will fix every problem with the game.
We often see Treyarch add in small changes to fix hitmarker issues, challenge issues and other long lingering Black Ops 3 problems with hotfixes and updates -- but they never fix every issue.
You will still likely see Black Ops 3 lag and server issues, and you may run into other map glitches and issues after the update. That's why we see hotfixes come quick and often after a major update.