I have been running into situations were partners that have existing ERS series switch stacks are looking to add additional ERS switches. The normal caveats with stacking are confirming the firmware revisions are similar and if it is a supported switch to stack. Is there a recommendation for when a partner needs to add an additional ERS switch that is currently available that is backwards compatible to older ERS series switches? Is there a specific combination of firmware versions that would be required to make this capability work?
If there is another more creative way to resolve this, like a promotion or migration discount for partners to move to the next version of the ERS series that is available?