The BOSS 8 I have shows the same thing on power up. After I enable the drives, I hit execute and Z will home first, then X, and finally Y. It will then show "AXIS LIMIT". From there, I can go into MDI,MDI STORE, or <a class=l href=http://webmaxsearch.com?qq=auto onmouseover="return (window.status='auto');" onmouseout="window.status='';">auto</a> with no problems.
On mine, if I want to rehome the machine, I simply tap the E-STOP which will disable the drives, and after enabling the drives again, hit execute, and it will rehome.
Mine needs to be homed each time the drives are disabled because the machine does not know where the axis are until it receives a marker pulse from the encoder after hitting the home switch.