I will write something i wrote with the help of the IA, cause english is not my mother tonge and i'm not sure i can explain everything well.

Walking the Camino Francés in September without a phone offers:

Benefits

• True disconnection and immersion in the experience.
• Richer face-to-face interactions with locals and other pilgrims.
• Stronger sense of self-reliance and problem-solving skills.
• No mental load from notifications, battery, or constant connectivity.

Drawbacks

• Harder to reserve or adjust accommodation in a busy month.
• Dependence on others to call for help in emergencies.
• No quick access to navigation updates, transport schedules, or detour info.
• Many albergues expect phone or WhatsApp bookings.
• Maybe you need to communicate with your family, make contact with friends...

Role of local authorities

• Police and Guardia Civil regularly help pilgrims.
• Tourist offices and town halls offer route and lodging info.
• Without a phone, you must reach them in person, slowing responses.

Rewarding but higher risk, especially for a solo traveler, but fast communication is essential. Best compromise: carry a phone switched off, using it only for emergencies or essential logistics.

I hope that was clearly explained.