New Deck

Live in British Columba,Canada. Having a new red cedar deck installed. Contractor has already put Behr penetrating oil on the new wood.He did this in his heated workshop before he is going to install. After reading the forums sounds like he should have waited til the spring. Will this cause a longterm problem or just mean that I will likely have to clean and reapply after one season?As well now that he has applied in the warmth how long should he wait to finish deck outside as temperatures at night are  well below freezing.