Our change management team worked closely with the project managers who were leading the effort and would assign out things they needed in the project team meetings that consisted of all workstreams. There were a lot of different workstreams and only a couple dedicated change resources, so they were not able to be involved with all the different meetings. The workstreams would complete the requests and return them to change management, but everything was guided by change vs. the workstream itself. This seemed to work well apart from project management asking for items then a month or so later change asking for something similar, but just enough different that the workstream would need to revisit it again. Alignment of PM and CM requests was a big take away from our lessons learned.