We have a like situation in out VMS environment. They want daily
incrementals, monthly archives kept for a year and quarterly archives kept
for 10 years. We set up 3 management classes. One for the daily incremental
backups. One for the monthly archive with a retention of 365 days that is
scheduled once a month. Then every third month, instead of archiving to the
monthly management class, it archives to the quarterly archive management
class. The archives take a long time to complete because it has to move all
the data to tape, but it works OK.
        In the VMS environment, there is not support for the scheduling
piece of ADSM, so we wrote some scripts to figure out which management
classes the archives should go to, build the backup commands and run them
through the ABC client. If your client supports scheduling, you should be
able to schedule the archives through the ADSM server. (perhaps).

Ben