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Your LimeSurvey version: 6.3.1
Own server or LimeSurvey hosting: own server
Survey theme/template: custom based on skelvanilla
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I am experiencing something similar like the person in this post .
Let me describe the situation: I implemented a custom solution for a time constraint for a survey, after the time runs out the participant should be "rerouted" to the endtext.
I have Javascript in the client to count down the time and with an ajax function to a php script set the tokens lastpage behind the "last question" (so in a survey with one question, I set lastpage to 2) and I set a submitdate which should set the Token to completed (and it does).
In earlier versions like LS 3.X a "reentry" by "window.location.replace("/index.php/" + request_data.sid + "?token=" + request_data.token + "&newtest=Y");" "reloading" the page for the participant, they were brought to the endtext.

Now in LimeSurvey 6 even though I have "Enable participant-based response persistence" turned on, when reload the window a new response shows up (this behavior also happens if I don't set a submitdate). I assumed in the "worst case" when reloading with a completed token I should not be able to "reenter" the survey.

Which of the two behaviors is working as it should?

Best regards
 

What happens to "uses left" when a person is redirected to the end?

I think "Enable participant-based response persistence" is only partially relevant for this. It just helps you, that the person should get back into the same questionnaire if they stop and close the survey.

I think the most important part here is to make sure that "uses left" gets changed from 1 to 0 when the time runs out.

The "uses left" remained unchanged when it wasn't working.

I have resolved this issue by now. Apparently one should not set the submit date.