Config changes not picked up by Terraform

[neilalbrock]

I'm having a great time with this project, so first off let me say thanks for the great work! Now, to my question...

I've deployed a cluster with the following values set:

system_upgrade_use_drain = true
automatically_upgrade_os = true

However, if I change them to:

system_upgrade_use_drain = false
automatically_upgrade_os = false

The output of terraform plan suggests no changes are required. Is there an obvious reason this would happen i.e. can these only be set during cluster creation? Just looking to clarify before deciding what my next steps are. Thankfully I'm still pre-production with this work, so I can destroy and start over if required. However, I would want to be able to flip these settings back on afterwards so maybe I'd just end up with the inverse problem?

Any insights would be appreciated.