@Ken-Conrad Oddly enough, if you go to the "see other items" or "visit store" links, even from an existing directly linked item like those above, ebay claims that no items are available. You can only find the item if you already know the item number. (It really feels like I had to use the word 'item' too many times in this post.)

@Ken-Conrad @Mark-B They look perfect. And I suppose I can blame Chinese New Year for not being able to find these or anything similar. Looks like ebay hides all the items for sellers that go on holiday

The problem I've been finding when it comes to making a homebrew dock has been in sourcing headers to attach the Omega2s, assuming you don't want to permanently solder it in place.
Can't seem to find anywhere easily accessible (for Australia) that has 2mm pitch header sockets available for 16 pins (or even a combination of fewer pins added together). Or at least not without taking the price higher than it would cost to buy sufficient expansion docks directly from Onion.

Has anyone found a cheap source for 2mm headers? Either through hole or surface mount would be okay, would just need to adjust the circuit board to deal with what's available.

You theoretically shouldn't actually need to disable the AP to access the Omega2 from your network.
If the Omega is working properly, it basically pretends to have 2 network interfaces: one physical, using the MAC printed on the case; and one virtual, using a similar MAC number (usually starting with 42. instead of the 40. of the real one). It uses the virtual interface to connect to your existing network.

If you have Bonjour or similar service running on your pc, you should be able to access any Omega2s that are connected to the same network.

I had the same sort of problem, it also caused wired ethernet to fail completely. For the record, main network was on 192.168.1.x and was using a different wifi channel than the Omegas initially booted up on. Dual frequency, 2.4 and 5GHz Wireless-N.

Didn't find a resolution to directly use that network.

I was able to connect to my phone's hotspot at first, and ran the needed firmware updates via that. Still seemed to crash main network if I tried to connect to it.

Later on I dug out an old Wireless-G router and connected it downstream of main network (using a different SSID and with its own DHCP using 192.168.2.x). The Omega2+ and Omega2 are able to connect to the sub-network without causing further problems.