Interesting entry here from Guntis (MT Staff) (and subsequent posts about the same topic):
http://forum.mikrotik.com/t/v7-16rc-testing-is-released/177857/99
Basically, new configs should be pushed automatically.
It could be on your PC the new SSID is not directly visible (I also observed it already both on PC and Android).
DIsabling WIFI itf on the offending device, waiting a bit and then re-enabling wifi can help.
Otherwise it’s simply a matter of waiting just a while.
However, sometimes that doesn’t help either.
I noticed manually selecting the radio and hitting “Provision” button, can also speed up things.
Theoretically not needed, as indicated by Guntis, yet I observed it works in such cases.
BTW configuring wifi stuff over that same wifi link is probably … asking for trouble ?
Like cutting of a branch you’re sitting on.