Rheinmetall Skorpion, M41 90 GF, Cromwell B, T-34-85 Rudy, IS-2 and ISU-122S will all be available in the NA Server during August. I would assume other servers will get them too soon, so prepare your wallets if you want any of the rare tanks.
Aug. 1-22: M41 90 GF – Tier VIII German light tank
Aug. 18 – Sept. 5: Rheinmetall Skorpion – Tier VIII German tank destroyer
Aug. 26 – Sept. 5: Berlin Quartet – Cromwell B, T-34-85 Rudy, IS-2 and ISU-122S