Are the Pyke changes intended as nerfs?
On the PBE, Pyke has: Phantom Undertow (E) Bonus AD ratio increased from 80% to 110% Damage lowered from 95/130/165/200/235 to 95/125/155/185/205
Death From Below (R) Bonus AD ratio increased from 60% to 80% Execute threshold changed from [190-655 based on level] to [200-605 based on level] Full value: 200/250/300/350/400/450/475/500/525/550/575/590/605
If we do some math, we find out that these are circumstancially either buffs, power-nuetral, or nerfs On his E, the damage differential is 0/-5/-10/-15/-30 Which means, with the bonus AD buff, he'd need 0/17/33/50/100 bonus AD to break even. Looks like a buff at early levels, and nuetral/nerf (if he's doing really bad) at later levels. 100 bonus ad is pretty tight for a support, even Pyke.
On his R, the damage differential is +10/+10/+10/+10/+10/+10/0/-10/-20/-30/-40/-40/-40 So it is a definite buff before level 12, and after which it requires 50/100/150/200 bonus ad to make up the difference.
As near as I can tell, these changes buff Pyke at the early stages, and end up nerfing him at the later stages of the game (especially if he has less than 100 bonus AD). I can't tell if these changes are buffs, power-nuetral, or nerfs, my reaction would be buffs, since most supports live in the land of low-levels, but I can't say for sure.