Because Easter falls on Sunday 20 April in 2025, the
Camino Frances will experience a surge in pilgrims starting the following week. In a typical year, there is a surge in pilgrims starting the previous weekend - Palm Sunday - leading into Holy Week - Semana Santa. The week following Easter Sunday, is also very popular.
This surge will create challenges for accommodations in the first week or two.
The best way to manage the surge and its affects on demand for beds is to be somewhere else during that two-week period. There are a lot of threads here, and online resources to help you make plans and reservations.
Because of the dates this year, I advise making reservations at least from Saint Jean Pied de Port through Pamplona. Once you personally assess conditions on the ground, you can adjust your accommodation planning accordingly.
Many people make reservations for the next three-four or so nights in front of them. Then continue this pattern on a rolling basis.
As regards snow, the "official" policy is that the Napoleon Pass is CLOSED to pilgrims until April 1. That is a local government preogative, in both France and Spain, to protect the pilgrims as conditions can get treacherous.
But this date could be pushed back if there is still significant snow on the route. This said, I have walked the pass TWICE during the last week of April and have hiked though ankle deep, wet snow. I have also encountered similar snow fall at Cruz de Ferro in mid MAY.
I observed, on my various Caminos, and later confirmed through weather sources, that altitudes above about 700 meters ASL (above sea level) can experience significant snow in Northern Spain until the end of May. Consider this when making your plans, and be flexible.
As others have said, if the Napoleon Pass is closed due to snow, walk via Valcarlos.
Hope this helps,
Tom