When to purge patch log files

Is there a best practice for deleting patch log files in EBS?  I do the HRMS patching and the log files in 12.2 for adop are saved to the fs_ne/EBSapps/log/adop folder.  I know that actual patch files have to be kept until the adop cutover phase is run, but when is it recommended to delete the log files?  Once the patches are loaded in production and no issues are found, is it okay to remove the adop log files?  What are other users doing?  We have limited disk space so I want to keep the file system clean.