Fredy,
I have about 9 months worth of serious
mushroom farming under my belt, so I will give you by best guess as to what will happen--Nothing. I think that the spawn will sit there in their substrate and wait. If you are lucky, the odd weather (I live half way across the country, but your weather description sounds like a replay of my last month) will prevail and the little fungi will start to do their magic. I doubt you will have any major colonization by the start of spring, the normal time for spreading all that wonderful spawn, but you will have one great big advantage--you will have done it already. And with any luck at all, the newly added fungus will just be starting to do some of its magic, meaning spread, by the time the calendar turns to the time when you are told to inoculate. With luck, this means that you will have better colonization than if you waited.
I say that this is what I think will happen. Truth is, I am making an educated guess. I highly doubt that even if winter returns in earnest that anything bad will happen--the fungus will simply stop their growth. Again, I don't know this for certain, but I am pretty certain that is what will happen in the wild anyway--growth comes in fits and starts.
As I said, I have been working on this for the last 9 months, and I have put in a lot of effort--and learned a lot along the way. I noticed that at the beginning of December, my "chip bed" still looked like a bunch of dark colored
wood chips. 3 weeks later, with nearly daily temperatures getting into the 50s, rarely freezing, and rain, rain, more rain, then rain, and you get the idea, the bed has visibly decayed in just week's time. In fact, it is visibly more decayed today than it was one week ago. My point is that in the middle of winter, I plainly have fungal growth breaking down my woodchips into
compost (which, by the way, is my intended goal--mushroom compost. The Wine Cap mushrooms will merely be a bonus.
If you are like me, I would recommend getting a bit of bacterial action going in your piles as well
You might want to wait for another respondent who could confirm/deny my thoughts that the spawn will be unharmed if winter temperatures come back, but even if you go crazy and just do it, I strongly suggest you lay
straw or some type of "mulch" over your substrate to buffer the temperatures a bit.
It is good to know that there are others out there trying some of the same experiments I am. Let me know how your
project progresses.
Eric