Jan Suhr, his maternal grandfather is I-FGC58798 as well. https://www.jansuhr.se/slaktforskning/morfars-dna-visar-pa-vikingak...
Yfull, I-BY548, TMRA 1300ybp. I-BY548 > I-JN4 > I-FGC58798 (FGC58805 * FGC58798). I'm id:YF66172 (the first mentioned is "the other"). https://www.yfull.com/tree/I-BY548/