Solved

New tires wear fail!

Cosa hai provato a fare?
I tried to Practice in two different leagues; a 50% one and a 25%.
IGP1 SUPERFAST at 50% where I became administrador a couple of days ago.
CIGA ASCARI at 25% my own league created a couple of years ago.


Cosa è successo invece?
In IGP1 SUPERFAST the update was successfull with SS and H tires wear incresed of 2% and S decreased the same.
In CIGA ASCARI SUPERFAST the tires wear it's the double or more with all the compounds.

Il problema si è verificato durante l'utilizzo di dati Wi-Fi, mobili o entrambi?
Both

Il problema si è verificato nell'App, sul PC o in entrambi?
Both

Qual è il modello del tuo dispositivo?
LG G8S ThinkQ, precisely LM-G810EAW

Qual è il sistema operativo?
Android

Qual è il numero di versione del sistema operativo?
10, precisely V20o-EEA-XX

Quale sistema operativo ha il tuo PC?
Windows 10

In quale browser hai riscontrato il problema?
All

Può essere riprodotto il bug?
Whenever you want just making practice laps

Commenti addizionali:
I have screenshot of both Practice of the leagues

Hey ?
Different race distances have different tyre wear to try and make more options available at different race lengths.

As an oversimplification, 25% has the double of wear than 50%;  and 50% has the double of wear than 100%; with 75% in the middle of the 50-100% range.

This isn't a bug of the new balance changes. It's just tyre wear per race distance. What changed was the wear ratio between SS, S, M and H, and their pace. Hope you enjoy the new changes in different race distances. Ciao ?

Try you to make strategies with tires wear like this :

25%
Russia
SS 31%
S 21%
M 16%
H 13%

Doesn't have any sense. You don't know what you are talking about honestly. 

Sorry for not answering yesterday, kinda busy avoiding race  spoilers ?
Again, this is not a wear problem, it's the race distance wear ratio to give different stint lengths per tyre. Let me use your example:

This account races at 100% race distance and the last time I had a dry race in Russia (100% = 46 laps) the wear reported on SS was 11%, even before the balance change that gave them less wear. So, for me it would last 7-8 laps with ease, while if I could have this wear on a 25% race (11 laps), they could almost make the entire race without pitting, with S and M being able to do it a 0 stop in all tracks and still have pace. This would make H unavailable to use due to other compounds never losing performance and it being the slowest of all dry compounds.

To counter that, the game scales the wear according to the race distance. So if you have a 25%, 50%, 75% and 100% race, they would all have different wear per tyre to make more sense of the amount of laps each tyre can take and balance with pit-stops and strategies. If it wasn't like this, all shorter race distance with the same tyre wear of 100% would be a flat 1 stop, or even a 0 stop!

Take F1/F2/F3 sprint races for example, they use the same tyres of a full race to do 1/3 or 1/2 of the amount of laps, so everyone goes to the end without stopping because it's impossible to recover the pit-stop time loss with so few laps on these races.

I know, it's quite difficult to use softer compounds in 25% races, because you have few laps on them due to the high wear and few laps to recover pit-stop time, so usually the M and H are more used on them. But at longer race distances different tyres are better for each track, and they have a mix between harder compounds and fewer pit-stops and softer compounds and more pit-stops.
It may not the perfect balance, but it's a quite good one ?

You don't want to understand my point. 

You are trying to compare the wear between 25% and 50% race distances and I just explained why they are different. So what's the point that I didn't understand?

Once again, if you were comparing old vs new tyre wear and it was doubled in practice between 2 accounts on the same race distance, then it would be a problem and would need an investigation, but at different race distances it's the game logic to make use of wear ratio per distance.

The point is you don't have a bug, deal with it, if you don't like it write a suggestion

To the OP tyre wear is related to race length to make strategies possible, so your 25% Russian tyre wear compared to those racing with 100% race distance would be
SS - 8%
S - 5%
M - 4%
H -3%
They increase tyre wear as they reduce race length to make strategies possible, if not everyone racing in a 25% league would just use the SS tyre which could easily do 11 laps and 1 stop, this makes the other tyres useless.

I think it's you that doesn't understand the game mechanics

All you don't understand that in extremely competitive leagues all managers use tyres until tyres wear get to 40% lasting and maximum 2 laps under with low wear. So SS are never being used and will never be if you don't understand this you won't get my point. The past Saturday in Turkey in my 25% league we have been forced to do M M M or H H strategies for 13 or we were going to run on the rims. I repeat if in 50% the update canged of +/-2% the wear between SS, S and H that's fair; I could understand if in 25% race was going to change the +/-4% of SS, S and H wear but not over like it did cause is crap. Where is the spot of new different strategies will be allowed that you say! 

My own strategy in Turkey of the past Saturday

25% leagues are basically like racing in a quick race, with such a small amount of laps maybe 15-20 you need a car to be 1 second per lap faster to allow for a pit stop. It's common sense that people will choose a strategy to win, this could be start on the H and don't stop, you can race tyres to less than 40% easily, even down to 20% if it stops you having to waste 20 seconds in a pit stop.
If you want to add more randomness in the league you host just say all have to use 2 different tyres. It's what we do in out league but it's 75% so allows more strategies. Then people can't use M,M,M or H,H etc they could SS,H or S,M etc.