Another thing to think about. The Aragon valley is clay all the way to Obanos so the path can be very slippery if it rains. Prepare for this because there are not many options to stay between stages. Arres and Rueste are super stops.
Definitely prepare for bad weather (even snow!). That route has limited accommodations even during the regular “season” so definitely book ahead so you know what is open. We walked Pamplona to Lourdes (via Somport Pass) in May 2019: it was lovely except for the snowstorm at the summit!