First of all, I am making this post to communicate with the playerbase not with the devs. I have given up on the devs. They clearly do not play or test their games.
They have a bad reputation of ruining their past games like World War Z, Evil Dead, etc. The purpose of this forum is to only share and communicate with fellow players. 
They made $200+ million selling this game, they got more profit than they expected. Customers do not matter anymore once you get money in your pocket. 

Parry timings on fencing have been changed and the worse part is not the change but that they have failed to communicate about it. 
They will just say that it was part of minor fixes but something like this should be informed since parry is a huge core aspect of the game. 
So it's either a shadow nerf or an unintentional change which they did for dodges in the past and then reverted it.
They think players are lab rats and push whatever update and if players cry, just claim it as an unintentional bug. 
We are customers, wouldn't you be annoyed if you went to a car repair service and they changed the timings of gearbox?
That is how they treat their players. 

FENCING PARRY 
Before the update, in patch 4.5, fencing parry was broken and spammable. There was no need to time it and you could just spam it and always land parry.
You could stand in the middle of a horde and spam parry for infinite armor on minoris and gunstrike if a majoris happens to swing. 
So in a way, they are trying to change it without informing the players. Parry in any game should always have timings and before the update on fencing, it needed no timing but only spam. The change they have done for fencing is changing the riposte bonus window from 0.495 to 0 (same as balanced). 

Now, if you played Dark souls, riposte window has got nothing to do with parry window. So, I don't know why they label the terms incorrectly. 
Riposte is basically a Gunstrike which happens after the parry. If we ignore the terminology, the difference between fencing and balanced is : with fencing the "riposte" starts earlier than balanced but they both have the same window. So you cannot spam parry anymore like before. 

Considering what they said some patches ago about fencing parry starting early but having same window as balanced, this change corresponds to what they wanted in the previous patch but never implemented it properly. So now, players got used to the spammable parry and have to relearn it and devs do not care to respond to these events.

I am still testing all the parry mechanics with other players and very likely update this post if new information comes out.