Is the a way of configuring BLC to remove old clone records?
The enterprise module has a purge job available. The setup can be found in the config/bc/sql/load_sample_jobs.sql file in the Enterprise module. Basically it inserts the following record:
--poll the system every hour
INSERT INTO BLC_SCHED_JOB (SCHED_JOB_ID, TYPE, NAME, ENABLED, DATE_UPDATED, CRON_EXPRESSION, MANAGE_IN_ADMIN) VALUES (-122, 'SANDBOX_CLONE_PURGE', 'Deployed Sandbox Clone Purge', TRUE, CURRENT_TIMESTAMP, '0 0/60 * * * ?', TRUE);
This can be set to any time you'd like, but ultimately it uses the PurgeSandboxClonedEntitiesEventFactory and PurgeSandboxClonedEntitiesEventConsumer which are meant to clean up old clone records.