Here are the doc from oracle online document to clarify the FLASHBACK TABLE
Use the FLASHBACK TABLE statement to restore an earlier state of a table in the event of human or application error. The time in the past to which the table can be flashed back is dependent on the amount of undo data in the system. Also, Oracle Database cannot restore a table to an earlier state across any DDL operations that change the structure of the table.
Oracle strongly recommends that you run your database in automatic undo mode by setting the UNDO_MANAGEMENT initialization parameter to AUTO. In addition, set the UNDO_RETENTION initialization parameter to an interval large enough to include the oldest data you anticipate needing. For more information please refer to the documentation on the UNDO_MANAGEMENT and UNDO_RETENTION initialization parameters.
You cannot roll back a FLASHBACK TABLE statement. However, you can issue another FLASHBACK TABLE statement and specify a time just prior to the current time. Therefore, it is advisable to record the current SCN before issuing a FLASHBACK TABLE clause.
There are the prerequisites to use FLASHBACK TABLE
To flash back a table to an earlier SCN or timestamp, you must have either the FLASHBACK object privilege on the table or the FLASHBACK ANY TABLE system privilege. In addition, you must have the SELECT, INSERT, DELETE, and ALTER object privileges on the table.
//row movement shoud be enabled except flashback drop, cauze flashback drop is using the recyclebin instead of undo data
Row movement must be enabled for all tables in the Flashback list unless you are flashing back the table TO BEFORE DROP. That operation is called a flashback drop operation, and it uses dropped data in the recyclebin rather than undo data. Please refer to row_movement_clause for information on enabling row movement.
To flash back a table to a restore point, you must have the SELECT ANY DICTIONARY or FLASHBACK ANY TABLE system privilege or the SELECT_CATALOG_ROLE role.
To flash back a table to before a DROP TABLE operation, you need only the privileges necessary to drop the table.