Hi! I belong to R1a > YP350 > Y42739, and my Y-DNA ancestors were probably Yotvingians. I have joinded recently the YFull.
I am this guy who makes the research of J. R. R. Tolkien's genealogy and genetics, who discovered not only that the Tolkiens came to England from Prussia via Gdansk (Danzig), but also that the Tolkiens belong to the YP270 line. You can find my research looking for hashtag TolkienAncestry
At the moment we try to finalize the BIG Y of one of the descendants of the Tolkiens from London < Gdansk < Prussia: