I feel terrible. There was a mishnayos to be finished during shloshim for a member of my community who passed away. I agreed to learn a mesechta. Originally it said to finish by January 11. I finished it today. I went to look back at it and saw that it was changed to January 9. I’ve been researching when shloshim ends and see that it ended after Shacharit this morning. I finished before shkeya today. Does it count as if I finished in time? If not, what do I do? I feel terrible. Thanks
From what you are describing it sounds like you did just great. You took upon yourself to learn the mishnayos in time for the shloshim, and you did finish it on the thirtieth day. The fact that the aveilus finishes after shacharis, is because we have a rule that even if part of the day was observed, it counts as a whole day. Nevertheless, the day you finished the mishnayos was on time.
Even if you wouldn’t have finished on time, the actual learning of the mishnayos is the main merit for the niftar’s nishoma, which you did.
Therefore, you shouldn’t feel terrible, rather great, because you did this friend a great chesed shel emes.