Here is another reason for you to consider for why Yom Kippur is on the 8th and not on the 10th of the 7th month.
Let's take a look at the burnt offering required for Yom Kippur:
YLT Num 29:7 'And
on the tenthof this seventh month a holy convocation ye have, and ye have humbled your souls; ye do no work;
YLT Num 29:8 and ye have brought near a burnt-offering to Jehovah, a sweet fragrance, one bullock, a son of the herd, one ram, seven lambs, sons of a year, perfect ones they are for you,
YLT Num 29:9 and their present, flour mixed with oil, three-tenth deals for the bullock, two-tenth deals for the one ram,
YLT Num 29:10 a several tenth deal for the one lamb, for the seven lambs,
YLT Num 29:11 one kid of the goats, a sin-offering; apart from the sin-offering of the atonements, and the continual burnt-offering, and its present, and their libations.
Now, let's take a look at other Torah offerings and see if we can find a similar one:
YLT Num 29:35 'On the eighth day a restraint ye have, ye do no servile work;
YLT Num 29:36 and ye have brought near a burnt-offering, a fire-offering, a sweet fragrance, to Jehovah; one bullock, one ram, seven lambs, sons of a year, perfect ones;
YLT Num 29:37 their present, and their libations, for the bullock, for the ram, and for the lambs, in their number, according to the ordinance;
YLT Num 29:38 and one goat, a sin-offering; apart from the continual burnt-offering, and its present, and its libation.
So, as you can see, this is undoubtful evidence that Yom Kippur was originally on the 8th day of the 7th month, not on the 10th like we have it now!
This is so sad and frustrating. The level of blatant editing of the text by rabbis is simply unbelievable. The only thing that calms me down is the knowledge that whoever digs a pit will fall in it, meaning that rabbis felt victims to their own evil plan and now they themselves believe into incorrect information that they have made up to deceive the nations.