I'm sure someone else will soon provide information about having a package sent to you in Spain. In the meantime, perhaps you can think about an alternative approach...
You note that you "will need warmer clothes" at some point. I suggest that you will more often need the warmer layers that you might need occasionally (if at all) earlier in your trip. In other words, I would go prepared for an occasional chilly day in September, knowing that those days will be more frequent in October. So, what you might need in October is one more light layer so that you have the flexibility and guarantee of being able to layer up with dry clothes. Adding a wool buff, hat and gloves is another important way to stay warm. Choose a rain jacket that can serve as wind breaker and is roomy enough to take several layers underneath.
For a November camino, I would simply take my September equipment (which includes rain jacket, rain pants, and layers for almost any weather condition) and add one lightweight base layer (top and bottom), an extra pair of wool socks, a buff, and gloves. You could either decide to carry those things all the way, or buy them in SJPP or Pamplona, instead of bothering with the international mailing of a package. That will also give you the opportunity to become more familiar with your own needs and preferences for clothing combinations on a long walk. We all do things slightly differently, and we learn as we go!