Environment: This functionality was available from Service Desk version 7.2.6 onwards
You are able to make a particular attribute in a template overwrite other default values set for that attribute. For example you may have a default response level set but want the response level on your template to default to something different. You can do this by highlighting the response level attribute in the template whilst in template designer. You then click on the properties tab and select Overwrite? True or False. The Overwrite value indicates whether the template value should overwrite the attribute default.
For more information on creating templates please see this document and your designer manual: