dba_optstat_operations : lock_partition_stats status issues.

On Oracle 12.2 I have a 400GB sub-partitioned table. Today I decided to remove all the statistics. Re-collect the complete table stats with the following options, INCREMENTAL, method_opt => 'FOR ALL COLUMNS SIZE 1' and granularity => 'ALL'. 

I can see the dbms_stats has collected the full table, partition and sub-partition stats. What I have also done is locked the partition stats older than 2021-11-30.

After the above task was completed, I queried dba_optstat_operations, where I saw entries for the above table partitions where column OPERATION and STATUS has the values "lock_partition_stats" and 'IN PROGRESS' respectively; I was expecting the column, STATUS to say COMPLETED instead of 'IN PROGRESS'.