Thanks a lot for your help. Wife has income and husband has income as well. They live together in a house all the year. Husband has high income and also a S-corp with a high K-I ordinary income and gain. His wife just has a w-2 and they are ok to file individually. They are in Commu. Prop, CA.  Wife is my new client but husband is not my client. When I took a look at her last tax return, 2021 She filed as MFS that this is right and I see form 8958 Column A and B are almost same with a diffrence $1 for column C for her husband. All numbers on A and B are belong to wife and C belong her husband. 

My questions:

Since we could not recognize her previous tax preparer left unchecked or checked the box of :  Allocate community...let me know what does mean if we check or leave uncheck exactly at this situation. IRS will receive two tax returns from them but numbers are not correct, right? I mean column C.

At this situation do we have" Community Property Laws Disregarded happened"?

But pub 555 says 8958 must be filed, I confused.

In general, when one wants to have just only her/his income in his/her tax return in Community Prop what is the method MFS return. What docs should be attached? how about the box on 8958 YES/NO

This is a heavy burden on my shoulder that made my brain stopped.