It seems a range of packages are unreachable:

root@Omega-1A1C:~# oupgrade -check                                                                                            
> Device Firmware Version: 0.1.3 b328                                                                                         
> Checking latest version online...                                                                                           
> Repo Firmware Version: 0.1.3 b328                                                                                           
> Comparing version numbers                                                                                                   
> Device firmware is up to date!                                                                                              
root@Omega-1A1C:~# opkg install pyOnionI2C pyOledExp                                                                          
Unknown package 'pyOnionI2C'.                                                                                                 
Unknown package 'pyOledExp'.                                                                                                  
Collected errors:                                                                                                             
 * opkg_install_cmd: Cannot install package pyOnionI2C.                                                                       
 * opkg_install_cmd: Cannot install package pyOledExp.

I have noticed a failed signature on updating the package list:

root@Omega-1A1C:~# opkg update
...
Downloading http://repo.onion.io/omega/packages/Packages.sig.                                                                 
Signature check failed.                                                                                                       
Remove wrong Signature file.

Would that be the origin of the problem?