According to sources cited in Seder Hadorot, Tevet 28 is both the birthday and the day of passing of Shimon the son of Jacob; other sources place the date as Tevet 21. (See the entry for Tevet 21).
Shimon ben Shetach successfully completed the expulsion of the Sadducees (a sect which denied the Oral Torah and the authority of the Sages) who had dominated the Sanhedrin (Supreme Court), replacing them with his Torah-loyal disciples, on the 28th of Tevet of the year 3680 from creation (81 BCE).
Rebbetzin Chana Schneerson (1879 (O.S.) - 1964), mother of the Lubavitcher Rebbe, was born on Tevet 28.
On Yom Kippur, the souls return to connect to their origin, carrying with them the divine sparks from all they've done in this world.
Their return rises like an aroma of burning incense through the atmosphere, and through endless strata of spiritual realms, until it reaches a place beyond higher and lower. It reaches the essence of G-d.
And there it becomes the essence of pure and ultimate bliss.
On Sukkot, that divine, supernal delight reappears in our world, much as a cloud condenses from the vapor rising from the sea.
And it manifests as the branches and leaves covering our Sukkah.
So that within the Sukkah, we are embraced by G-d’s delight in us, and we rejoice.