And what VN might that be?
VNs are hard to make good animes of, since there are many plots.
Anime adaptation doesn't exist.
And that the many plots thing is actually one reason why LB! anime has a chance to fail. (Spoilers for LB! here) Until someone gets to Refrain, other than the upgraded stats of Riki and Rin, and Rin's social behaviour improving, there isn't much reason to believe that there is a timeloop going on and that the routes are connected.
But in the case of an anime, this will be obvious from the first time it happens. If they go the Clannad way (including all other heroine routes as subplots with Rin as main heroine, just like they did with Nagisa in Clannad), then the whole timeloop
factor will have to be discarded, as there will be no separate routes. (Even Clannad threw the "collecting lights"
part halfway down the crapper because of this reason.) And that will actually alter the story quite a bit. Even if they go for separate routes, the subtle differences in the common route in Rin's behaviour
will totally be lost because they won't be able to repeat the common route's part of the story like the VN does.
All in all, not really looking forward to it. Especially with the characters looking nothing like they did in the VN. Kinniku-less Masato? Do not want!