There are many players already aware of this and the effect is referred to "time dilation" by those I know, who know of this. This could be a feature as such effect occurs in a multitude of games as a way for servers to keep up with all the calculations occurring. Games such as Stormworks or EVE Online have this.
The time dilation in wolfpack can be both faster and slower than PC system time, If this is a bug or not, it's hard to say from my point of view.
If the cause of this time dilatation is due to the use of having in-game stopwatches actively counting in game or not should be explored. I only brushed it off as server calculating time slower as a result on high load.
Regardless the time dilation is not only representing itself on the time display itself. It actually will represent the actual time that the game session is running on regardless if there is a delay or a speed up. This can be seen by checking TTI before launch of torps and them watch when the impact happens. As far as I have observed torpedo simulation is accurate in sync with the in-game time and in-game stopwatches and you would only really notice a discrepancy with a IRL clock and im game time.
So as long as you do not use out of game clock/timers/watches/counters then you will never really notice the time dilation.
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/Fox🦊
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