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What happens as part of the change?
On December 121, 2020 (starting 8 p.m. CET) the current FileSender test system https://filesender-test.aco.net/ will become available at https://filesender.aco.net/, taking over from the previous/old system.
Between 8 p.m. and midnight that day neither system may be availble, so plan your FileSending activities accordingly. 
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