Can't see any easy way to change my language on the page. How annoying!
And, as it's stated in the FAQ [1], SMS option is only available in those countries at the moment, regardless of where you're located. When it becomes available in Poland, they'll text you and you can activate it. But until then, you can safely use 2FA without an SMS backup (as I did).
Now, I know that technically the area code for ALL mobile phone numbers is 04, so I split that up. Nope, SMS never arrives. Next I removed the leading zero from the area code so it would be formatted as +61 4 xxxx xxxx.
Those who are familiar with Telcos and the way phone numbers work internationally would eventually stumble onto the right solution. Still pretty shocking though.