I will add to this as I explore, but first up my findings.
There is an 'event' for
- membership is added
- membership is changed
There is an 'action' for "add to group" which allows adding to single or multiple groups.
AFAIK there is no Condition yet for
- Membership type
- membership status change
Also checked out if I could make the Rule based on the Activity that is generated when someone Expires eg
- Activity Type = Change Membership Status
- Activity Subject = Status changed from Grace to Expired
While the former exists, the latter doesn't so I can't see that I can currently build the Rule off that.
So either way looks like we need to add some new Conditions. Will update on progress