TK,

If you get a moment, would you please look at the pic. Of the SEP and tell me where the power to the panel can be shut down?

I don't see anything but active CBs.

Don, I don't mean to answer to TK, but I replied to this in post #9.
This is a condo. It is typical to have main lug panels with the main service disconnects at the meters or maybe in an equipment room so they can all be grouped together.

There is NO main shutoff AT this panel, nor is one required.