Hi Camino Chris, welcome to the forum. I walked during Holy week in 2015 - started the week before from SJJP. I experienced no difficulty getting accommodation in Pamplona, but after then it became tricky. As others have said the weekend of holy week is when lots of Spanish people walk the Camino, or sections of it. Accommodation at Zubiri was hard to find but we arrived around teatime, the albergue at Uterga (after the Alto Perdon) was full, but I had reserved a bed by booking ahead. The Refugio PP Repardores at Puente La Reina had lots of beds but you needed to arrive no later than around 2pm to secure one - it's a great place to be for Holy week having three magnificent churches all open to the public and with Semana Santa processions. The Los Arcos albergues were full that weekend, but there was private accommodation available - book ahead for peace of mind - and the street processions and tableaux were wonderful. I don't know how far you intend to walk each day, but if planning to cross the Pyrenees via the Napoleon route and stop at Orrison you will definitely need to book to secure beds there. If you walk via Valcarlos, there is a small albergue but I don't think they take reservations but there is other accommodation in the village. I stayed at a good private place in Espinal called Haizea, where myself and a fellow peregrina were the only pilgrims there. As others have suggested, book ahead where possible to ensure beds for the four of you and then enjoy the holiday. Buen camino!