Hi, Jaekae,
Welcome to the Forum!
Absolutely there is no way to give a vote that would be anything other than a guess based on nothing. Some years, lots of snow, some years, no snow (or manageable snow).
If I were you, I would start with the plan of walking from Leon. When you get to La Robla, where there's an albergue, find out what the weather conditions are. You may be lucky. One way to get help on this topic is to post a question on the Camino del Salvador's Facebook page a day or two before you have to decide. The man who runs the Facebook page, known as Ender, is very attentive to questions and up to date on weather conditions. (He is also the man you will thank many times as you walk across a multi-km mountain stretch where there are now metal arrows and conch shells to lead you, thanks to his efforts).
Buen camino, Laurie