I know you are trying to trace your family in Poland/Belarus who are alive today.
If you look at KARTA again where you'll see so many Siedleckich there, but the difference is that Karta has added some dates which were not there last year.
You'll see Henryk son Wincentego 1916 who was repatriated to Biala Podlaska in 1946 , but has an added date of 1990.
So was Witold son Wincentego born 1925; Boleslaw son Stanislawa b 1905.
If your family came from Bilostockie then I would guess that they might have returned to near where they came from. Biala Podlaska is just West of Brzesc, but in Poland and not in Belarus. It is South of Bialystok .It is worth persuing that route as well.
I do not know if Group has noticed that some changes have been made to Dane Osobowe in Karta Indeks Represjonowanych and I am not sure why newer dates have been added. As late as 1990.
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