If you got them early Feb, I think you isolated them more than long enough, especially if you don't see any problems!
I usually put my new ones with the rest of the orchids right away, unless I have a doubt on the health of a new one. Then I just leave it aside for 2 weeks or so, just to see that there are no problems appearing.
__________________ Camille
Completely orchid obsessed and loving every minute of it....