Can deregistering building affect common areas and open spaces?

I purchased a 1RK flat in a residential project. The overall project has 5 buildings, each with 12 floors. However, the builder received RERA approval for 3 buildings in 2018, with December 2022 as the completion date. Due to the pandemic, he was able to complete two buildings (C and E). Now, building A has been under construction. The builder started going door-to-door, urging residents to sign a self-declaration form suggesting that residents in buildings C and E have no problem with the builder deregistering building A from the project as per RERA and are aware of the consequences. All this was being done without informing the committee. When asked about the consequences, his men gave evasive answers. The building handover, conveyance deed process is not completed. Can deregistering building A lead to problems in common areas and open space available for us. What questions or information should we ask the builder to share with us before signing this no objection document?