The more you think about the logistics the more crazy it gets . In addition to dithering by us, you have time zone issues, global language issues, the natural reticence in paying upfront for accommodation, and I bet a unique set of peaks and troughs in planning, correspondence, booking etc.
I guess our expectation is for a direct, automated online booking system, with the required language mix, available 24/7/365 with payment facility, that alerts pilgrims if a cancellation allows a space to become free, alerts sent based on a specific algorithm that contacts earliest enquirer first allowing them 24hrs to respond - or perhaps all enquirers at the same time - first come first served basis?
Not very Camino , more hotel than Alberque and my brain now hurts