This restriction disappears in Cloverleaf 5.6.
It is still a good idea to archive your SMAT fles as Troy indicated as that gives you the ability to research/resend/etc. messages right from your platform without having to get the Tivoli Admins involved for a restore.
You can also customize the size of your archives by thread by cycling and archiving on different frequencies.
email: jim.kosloskey@jim-kosloskey.com 30+ years Cloverleaf, 61 years IT – old fart.