Let's say you have someone who already filled out a screener with a scheduling question, but you want to email them to invite them to either click on a new URL, or pick new times since they filled out the screener.
Before you are ready to invite previous respondents, make sure to customize the "Invite Previous Respondent" email under Scheduling >> Emails, because that's the email they will receive when you click send.
After you have your "Invite Previous Respondent" email setup, you can go to Responses and check the box next to their name. Then click the Invite Previous button right above the list of participants.
You can now select up to 100 people at a time. Then click the Send Email button.
This will not require them to answer any new questions on the screener except to pick a new time. They will receive an email asking them to pick a new time, and then will see a page like this, but keep in mind there must be a scheduling question present in your screener, although you can hide it if you don't want initial respondents to see it.
After they have responded to the scheduling question, you can invite them from Scheduling >> Calendar.