What Happens with no sim

[Sunrit Chroma]

Other than no calling or texting what happens if you have no sim card inserted into a wp 8.1 GDR1 developer preview device
is there too much functionality lost. will the time stay in place
thanks if u answer
BY the way I am on a lumia 820
IDK the country variant because i bought it from amazon

 

[Pacus1x]

Everything will work, except like you said calling, SMS and mobile data.

The time will stay, you can set it automatically in Settings and the WiFi on.