So I needed to switch RSI Notification plans on hundreds of our alarms because they were created (before my time) with the default plan which can't be edited. Apparently there's no such method neither in the RSI or RSC control panels.

So I had to:
- install and configure rax CLI (I'm on OSX)

sudo pip2 install rackspace-monitoring-cli

nano ~/.raxrc 


[credentials]
username=YOUR_USERNAME_HERE
api_key=YOUR_APIKEY_HERE
  
[api]
url=https://monitoring.api.rackspacecloud.com/v1.0
  
[auth_api]
url=https://identity.api.rackspacecloud.com/v2.0
  
[ssl]
verify=true

- change the plan: 

raxmon-notification-plans-list #choose your new plan from output and set in $new_plan=

raxmon-entities-list > rax_entities

$new_plan= ; for e in $(cat rax_entities | cut -d ' ' -f 2) ; do for a in $(raxmon-alarms-list --entity-$e | grep 'id' | cut -d ' ' -f 2 | sed 's/,//'); do raxmon-alarms-update --entity-$e --$a --notification-plan-id=$new_plan; done ; done

BR,

M.