bug: Date extend mode not working when edit date

[sk5s]

Prerequisites

• [X] I have read the Contributing Guidelines.
• [X] I agree to follow the Code of Conduct.
• [X] I have searched for existing issues that already include this feature request, without success.

Countdate version

v1.5.7

Current Behavior

When date extend mode is on, it only works when adding Countdate not when editing.

Expected Behavior

When date extend mode is on, it works when adding Countdate not when editing.

Steps to Reproduce

No response

Additional Information

No response