As time passes, and current rows become history rows, you should periodically use the ALTER TABLE TO CURRENT statement to transition history rows out of the current partition into the history partition. ALTER TABLE TO CURRENT resolves the partitioning expressions again, transitioning rows to their appropriate partitions per the updated partitioning expressions. For example:
ALTER TABLE temporal_table_name TO CURRENT;
This statement also updates any system-defined join indexes that were automatically created for primary key and unique constraints defined on the table.