Why do tank crew positions change at the start of the game?

Every time I start the game, the tank crew positions switch automatically. I play on the Japanese side.

Does anyone have this problem?

The game automatically selects the crew with the best suited perks for a certain task. On your pic on the bug report site, I see your machinegunner and loader are changed in position by the game. It may be because of the perks you have selected for them, are not best matching for their task.