This can be accomplished by using either the rule builder tool or with a C# Script.
Rule Builder
1. Log into your Crossware portal > Click on the Rules icon in the sidebar menu > Select Create rule
2. Enter a rule name and a description for the rule > Select the BUILDER tab > Click on the DATE option and fill out the fields according to your request (e.g., Christmas campaign for the entire month of December) > Select SAVE & CLOSE to save the changes made.
C# Script
1. Log into your Crossware portal > Click on the Rules icon in the sidebar menu > Select Create rule
2. Enter a rule name and a description for the rule > Select the CUSTOM tab > Insert the C# code accordingly (the example below is for the Christmas campaign throughout the month of December) > Once you are happy with the code, click SAVE & CLOSE to save the change(s).
Applying the rule to a signature / signature block
Applying rule to a signature:
1. Click on the Signature configuration page
2. Hover your cursor over the relevant signature > Click the Edit button
3. Under the Who is this signature for? section, click the drop-down option > Select the Rule option
4. Click the Select a rule drop-down option > Select the recently created rule
5. Click Save & Close
Applying rule to a signature block:
1. Click on the Signature block configuration page
2. Hover your cursor over the relevant block > Click the Edit button
3. Under the Who is this block for? section, click the More options drop-down > Select the Rule option
4. Select the recently created rule > Click Save & Close