The issue is simple. I've been getting something like 17-20 LP for win for the last, let's say, 2 weeks (30-60 games?), losing about 15 LP. Now, I downloaded new patch, about 3 hours ago, and played two games. I won both of them, however I got only 12 LP for both, friend I played with got 15, he was also getting 17-20 before patch. Not only that, people we played against claimed that they lost, in the first game, 24 LP, and in the second 27. I checked their op.gg, and they were not on losing streak of some kind, that would threw their mmr into shithole.
So yeah, I guess there is some problem with LP gain/loss.
Did anybody else experienced that?