How will work ? downloadable later or at the release time?

The first paid expansion is supposed to arrive in October, the second one in early 2016. So nothing to download at release.

Since there's no pre-order bonus involved for the expansion pass I personally won't preorder it right now, but rather sometime this fall. ;)

atm proly at release date of the 1st expansion(some day in october) ,but might be some early access if u got the witcher complete collection as a reward for ur support, myself i wont buy it till around september unless a good deal comes along before that

ah yes! sorry i've read now the details on the expansion, but thanks for the replies!