Kandly, Community Coordinator, wrote this on the EU forums here:
Some clarifications regarding this: In order to display the information, we’re using the files in the game client, in which we put a number of values that pertain to vehicles.
As you know, in update 9.17 we introduced a new mechanic for some of the Swedish line tanks: Siege Mode. For these tanks, we have created an additional (secondary) file in order to adjust the Siege Mode’s settings. The game client uses a number of settings from that file, which are only connected to the Siege Mode. The client uses all other settings – only from the main file.
With the Strv S1, we have put a number of parameters into the secondary file, bearing arbitrary values from the main one – and because these parameters do not influence anything when in the file, we weren’t able to quickly remove them from it.
These are the parameters we are talking about:
• Ground Resistance
• Braking Power
• Hull Rotation Speed
Because of this, third-party services displayed incorrect parameters of the Strv S1 starting with the release of the vehicle in update 9.17.1, which was caused by the aforementioned arbitrary values in the secondary file. That being said, the game client was nevertheless displaying the correct characteristics.
In update 9.19, we have finally removed the troublesome parameters from the secondary file. As a result, third-party applications started correctly displaying the real values.
To conclude, the above parameters of the Strv S1 haven’t changed since the release of the vehicle.
For correct comparison of this vehicle: Compare Siege Mode with Siege Mode values, and Travel Mode with Travel Mode values.
Regarding the time of switch from Travel to Siege Mode:
From the release of the vehicle in update 9.17.1, the switch time from Travel to Siege Mode was displayed as 1.25 in the Garage, while you could see a more precise 1.3 while in battle. In update 9.19, we decided to fix this discrepancy, but unfortunately did not inform you about it.
Thanks for being attentive to detail and your prompt feedback!
My take on it: WG tries to hide game bugs under the carpet, pretending they did not happen and blaming everything on the third party stat reader tools. At least they are trying to fix the issue, so we got that going for us.