In user segments, relative dates and periods are very crucial when you are building your lists. For example, when you want to choose visitors who visited last month or signed up 3 months ago and so on.  Now you can do that in Zonka Feedback too.

Introducing Relative Time-Period in User Segmentation. Now, you can easily narrow down dynamic segments with date-based attributes using relative dates such as "is less than", "is more than" and "is exactly". These would work with attributes like Created Date, Updated Date, Last Seen Date, and all custom date-based attributes. You can use rolling dates such as 'this week', this month' or 'next quarter'.

For example, 

• If you want to show a popup survey to a logged-in user who was last seen more than 15 days ago you can set your filters as follows: Last Seen Date - is more than - [15] days ago.
• If you want to show a survey popup to users who have subscription renewal coming in the next week you can set your filters as follows: Next Renewal Date - is rolling date range - next week