Microsoft have released a support document to help businesses affected by a bug in iOS 6.1 that is causing increased CPU, memory and bandwidth usage and reducing server performance.
It isn't know how many iPhone and iPad users are being affected by the bug however both Microsoft and Apple have announced they are working to resolve the issue. The problem is affecting companies using a full Exchange server (in-house or hosted) or Office 365.
Microsoft's advice is to begin by restarting the iOS device and then avoid processing Calendar items such as meeting requests until a fix is released. If that doesn't resolve the issue then ther user should remove the Exchange account from the device and have the IT administrator perform a 'remove device' command on the Exchange server. After 30 minutes the iPhone or iPad can have the Exchange account added again.
If the issue still persists the more drastic action is necessary, leading up to removing the Exchange account permanently from the device until Apple issue a software update. If your Simply Mail Solutions hosted email is being affected by the iOS bug then please contact our support team.