Greetings to you, my fellow planner. I am totally anal about how far I am willing to walk and what my lodging entails, so I understand your mindset more than most. To me, nothing is more stressful than having to walk another 5-10k to the next town, or sleeping on a mattress thrown on the floor in the corner. That being said, our last Camino (the Primitivo) was May/June 2024 and I had 14 of the 20 nights booked by the middle of October of 2023. Almost all of those stays were booked directly with the alburgues (most of which we had stayed at the year before) through their websites. I did book a few places on booking.com but only for ease of use. There were several places that politely let me know that they did not accept reservations that far in advance and asked me to reconnect after the beginning of the year. In one instance, they replied that the new year's prices had not been established, so I booked on the contingency that the price increase wasn't too drastic.
I would say that it is okay at this point to reach out, especially if you have locked into some key places. The worst they can say is to check back, and at best you will have one more lodging confirmed. We did the Portuguese from Porto in 2016 when the infrastructure was still limited, and I booked most of our stays at hotels through booking.com. Back then, I was not as learned in discovering alburgues, but I still did that at least 4-5 months in advance.
Best wishes and happy planning!
Bom Caminho!