My father-in-law was niftar 20 Marcheshvan, and brought to kevura in EY and the kevura was at night of the 22nd, while it was still 21st back in the States. My brother-in-law flew with the niftar to EY for the kevura while everyone else stayed behind in the States. Then he went back to the States to finish sitting shiva. His rav gave him a psak that since my mother-in-law is the gadol(a) habayis, so he was nigrar after her and had shiva shortened by 2 days and got up with everyone one else who stayed there.
So our question is, does that also apply to calculating shloshim? They counted from the day of death, but I see the Shach and Taz say count from burial and all the kitzer seforim just quote the Shach and Taz.
From the parentheses in your answer online it’s mashma the psak re shortening shiva will affect the cheshbon of shloshim as well. Is that correct and it does it indeed end on 20 Kislev?
Thanks and tizku l’mitzvos!
Hamakom yinachem eschem btoch shar availei tzion v’Yerushalayim
The shloshim is calculated from the time of the burial, even if some of the people, even the gadol habayis, started earlier. Therefore the shloshim ends on 22 of Kislev.