Looks like our predictions about OUATinWL being a mini series were correct. According to Adam, 13 episodes were ordered.
Isn’t 13 what most new shows get, though? They had a lot of confidence to pick up OUATinWL with only 19 minutes of the pilot filmed, sure, but that’s still a tough timeslot for ABC in the recent years, so it’s natural they’d want to wait and see if the show does well.
Also, I believe I’ve heard that a Q&A on the show’s page in Facebook revealed that another season could be made if people liked it. After the original idea to use this to bridge the two halves of ONCE’s season 3 was dropped, who knows what else of the original concept hasn’t also changed as well?