I am assuming that your LLC is being taxed as an S-corp.

If that is the case then this is all covered under IRC 1377.

The general rule for shares transferred during they year is that attributes of the S-corp will be prorated on a calendar day basis. So the original shareholder would get 264 / 365 of 20% the income of the S-corp and the succeeding shareholder will get 101/365 of 20% of the income of the S-corp.

However, there is an election to close the S-corps Books on the date of transfer and report the actual results for the periods 1/1 - 9/22 and 9/22 - 12/31 to the 20% shareholders.  This requires the approval of all shareholders and the corporation.

https://www.law.cornell.edu/uscode/text/26/1377