Best Price to get Stalingrad pre-order

I am interested in pre-ordering AA Stalingrad but I’ve never pre-ordered any game before. I know it’s coming out in August this year, when is typically the best time to pre-order to get the lowest price? Obviously there is a little guesswork here but based on what was done for North Africa and other AA games, when would be the likely best time to pre-order to get the best price and from what sites? The best I could see was $64 but I saw someone say they pre-ordered for $44.