We encountered some strange bug when using SOGo with mailcow and are not sure, if it is SOGo or mailcow related. Therefore I am also not sure yet, if it is reproducable on other systems. Here the reference on mailcow's GitHub: https://github.com/mailcow/mailcow-dockerized/issues/195

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When setting up a vacation mail by date in SOGo the first time everything seems correct and the sogo.sieve is created with the correct dates.

However on the next day the dates in the SOGo interface just "move" forward. So when I created a vacation mail yesterday with 2017-04-14 to 2017-04-18 the interface today shows me that it goes from 2017-04-15 to 2017-04-19 while however sogo.sieve still has the initial correct dates. But when I now update/change my vacation mail settings and save them the sogo.sieve will always have a offset of one day. No matter what I tried so far I cannot eliminate this offset and I'm guessing (due to problem reports of some users) that this offset gets bigger from day to day making it impossible to set correct vacation dates.

So far I don't know what causes this and if more than the vacation mail is effected.

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