Can I temporarily disassociate a domain and then reassign it again?
You can disassociate and then associate again a domain without a problem. In order to disassociate your domain please follow the next steps:
2. Select "Associate Domains" from the menu
3. Under associated domains click on "Remove" button for the domain that you want to disassociate
Can I still use the image credits associated with the removed domain?
Please note though that while the domain is not associated with any account it will default to the free credits. That means if these were used then, the CDN will not return images but rather will redirect to original, not-optimized images.
Also, please wait 5 minutes in between associations for the changes to take place.