For now, this is only some preliminary information, not a complete answer. I previously used comments to the questions for these, but the amount of information is geting too extensive for that.

> [Piotr Eberhardt. Political Migrations in Poland, 1939–1948 (2006)](https://web.archive.org/web/20111018004836/http://www.igipz.pan.pl/zpz/Political_migrations.pdf) has on p. 24 a table of where settlers came from and where they went:

[![German population settled until 15 September 1944 on Polish lands incorporated into the Reich][1]][1]

According to him, of the ca. 36,000 persons settled in (eastern) Silesia, about 30.000 came from [Bukowina](https://en.wikipedia.org/wiki/Bukovina_Germans). Note this is only one of several attempts to give numbers, and they differ widely, as the [Wikipedia article lists](https://en.wikipedia.org/wiki/Heim_ins_Reich#%22Heim_ins_Reich%22_in_occupied_Poland_1939%E2%80%931944).

The broader context, as explained in the same article, is the relocation of ethnic Germans (["Volksdeutsche"](https://en.wikipedia.org/wiki/Volksdeutsche), from outside the borders of the German Reich) from the influence sphere of the Soviet Union as defined in the [German–Soviet Boundary and Friendship Treaty](https://en.wikipedia.org/wiki/German%E2%80%93Soviet_Boundary_and_Friendship_Treaty) to Eastern Poland (["Heim ins Reich"](https://en.wikipedia.org/wiki/Heim_ins_Reich)).

One target areas for settlement in [Eastern Upper Silesia](https://en.wikipedia.org/wiki/East_Upper_Silesia) was the [Landkreis Saybusch](https://de.wikipedia.org/wiki/Landkreis_Saybusch). A Nazi propaganda calendar about the resettlement effort is available online:

> [Heimatkalender des Beskidenkreises Saybusch 1941, Jg. 1](https://www.sbc.org.pl/dlibra/publication//194728/edition/183439)

Don't expect veracity from that. It very obviously downtalks the conditions for Germans in the areas they were resettled from, and promises a bright future in Saybusch.

Among the few usable informations is the area that the settlers of the year 1940 came from (p. 350 of the digitization): the towns of Felizienthal, Annaberg und Tucholka. Other towns mentioned are Smorze (westwards), Karlshof and Klimiec (southwards towards the Hungarian border). On p. 379, it says that a total of 3013 persons were settled on 629 farms with a total area of approx. 10,000 ha. (The text uses the unit `vha`, which stands for "Viertelhektar" (quarter hectar), derived from the older unit [Morgen](https://en.wikipedia.org/wiki/Morgen).) This would amount to an average of 16 ha per farm.

A modern scholastic work about resettlement to Eastern Upper Silesia is

>  Hans-Werner Retterath (Hg.): Germanisierung im besetzten Ostoberschlesien während des Zweiten Weltkriegs (= Schriftenreihe des Instituts für Volkskunde der Deutschen des östlichen Europa; Bd. 20), Münster: Waxmann 2018.

The editor has made an [extract](https://waxmann.ciando.com/img/books/extract/3830988281_lp.pdf) available online. This [review](https://www.sehepunkte.de/2021/02/33491.html) identifies the settlers as Volksdeutsche from Galicia and Bukowina.

  [1]: https://i.sstatic.net/2fnjDiOM.png