Managing Demand around legacy ERP - tips & techniques?

I have a non- technical BPCS related query that I would welcome this group's input on. I am looking for any tips and techniques you and/or your organisations employ in the area of Demand Management (i.e. user request changes/enhancements) in relation to your ERP systems. I am particularly interested in legacy ERP.

The reason for my query is my organisation is looking to put together a structured approach to manage demand to operate across a number of ERP platforms. The one I support is BPCS (sys 38, v3.6 - so it's pretty old!). To date we have operated an ad hoc approach;
* User raises a request
* Our group assess the request to determine the level of BPCS development required
* Subject to approval we then proceed with development, testing and eventual deployment

Going forward we are being challenged to come up with a more structured approach to managing user demand. In addition instead of deploying enhancements on an ad hoc basis we may also consider moving to a release cycle, whereby changes would be 'bunched' together and implemented in a predetermined timeframe (e.g. quarterly). To complicate things further this approach is to be adopted across a number of ERP platforms, not just 'my' BPCS environment

I would be interested then in seeing if how you deal with Demand Management and also Release Management as it relates to your environment -e.g. what challenges you faced in developing and implementing these processes, lessons learned, what you might do differently were you to start all over again etc.


Kind regards,
John.