See enclosed screenshots. On the 2-nd screenshot, you can see: On the left - my source data - a time is 0115xx On the right - the data as exported by History manager. Pay attention that the time is now 0451xx , data is the same.
On the bottom - the data as see by History manager. A time is 0451xx, which shows, that time is shifted duting import, not during export.
My local time is currently UTC +3. I tried GMT+3 to bias the shift ,but then got a shift 1 hour back (the 3-rd screenshot).
I succeeded to import without a bias, only when importing a data as may local timezone (the 4-th screenshot) , REGARDLESS A DAYLIGHT SAVE TIME.
I got lost. It means that if I really what to import the UTC data as may local time data (which is most logical for my tests) I should perform copmutations how to cheat the history import mechanism in order to get the bias I need.
I think that instead of the existing, you should provide options:
1) to import without a bias
2) to import with user chosen bias (e.g. +3 hours , -2 hours ) etc...

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