Q. If someone has yohrtzait on Shiva Asar Betamuz, but because of old age he does not know if he will be able to fast a full day, can he be called to the Torah on this year during an early Mincha as he always is? He has always fasted before, yet he is afraid this year.
A. on a similar question 5036 we wrote:
“Mishna Berura (566: 19) quotes Magen Avrohom that the ruling of the Shulchan Aruch not to give an aliyah to someone not fasting applies only during Mincha but not during Shacharis in the days when there would be otherwise also Kerias Hatorah such as Mondays and Thursdays.
Mishna Berura quotes other Poskim that debate the issue, and summarizes, that is he was called to an aliyah according to everyone he should proceed.
Although. it isn’t clear from his words if he can be called lechatchila to the Torah, Aruch Hashulchan (ibid.), Divrei Shalom (93) and others rule like the Magen Avrohom and Eliahu Rabbah that he can be called on the onset.
Horav Shlomo Miller’s Shlt’a opinion is similar.”
Horav Shlomo Miller’s Shlit’a pointed that since Shiva Asar Betamuz, is on Tuesday (2024) and there is no usual reading of the Torah, there is more reason to be stringent, yet it all depends on the case, the changing particular circumstances and the feelings if he can actually fast the whole day.”