<p>Not the requested answer but related to the problem.<br>
If you change to 70D or 6D they have embedded Wi-Fi<br /> We use a 70D with EOS-Remote to send files from camera to a smartphone using Wi-Fi (only JPEGs, automatically downsized to about 2MB) and then we use WhatsApp to send photo from the smartphone to the customer (I think downsized again). Not the best quality but it takes only a few seconds per photo.<br /> Eos Remote has other options about destination.</p>
<p>About pigeons, there is a tech document (RFC 1149) about using pigeons to transport IP frames but it was written on 1st april (as other tech documents jokes).</p>
<p> </p>