How to understand if you need Confirm Version 15.20c

Product Feature: Installation / Upgrade
The main remedy provided by the 15.2c release is to fix a bug that was identified with the "Street Works Notice List'. The defect found in 15.2b was Confirm crashing when using the Find Street Works/List/Street Works Notice List. 

Street Works Notice List

If this is a utility on which the customer is fairly reliant, then the chances are that they will need to upgrade.
UPDATED:  September 27, 2017