Problem with datetime format used in %date% environment variable in Windows scheduled tasks

Recently I've faced with interesting problem. Let's say you have Russian datetime format set in Windows (Control panel > Region > Formats) and create new Windows scheduled task which runs the following cmd script:

echo %date%

It will use Russian datetime as it should. Now we change OS datetime format to English. If we will run the same script manually it will immediately use new format. But if we will run our existing scheduled task it will still use old Russian datetime format. Even if we will restart OS and will try to run scheduled task again result will be the same: it will still use old Russian datetime format.

Solution which I found so far is to recreate scheduled task (export it, delete and then import). After that it will use current (English) datetime format.