Just an idea...try setting the “urbanity” to itself in the survey flow after the JS runs:

urbanity = ${e://Field/urbanity}

Thanks for the idea! I’ve tried and will soon report whether it works. I now define urbanity twice in the survey flow: once at the beginning (without assigning any value), and a second time after it has been assigned by JS, using “${e://Field/urbanity}”.

Unfortunately, this is not working. The quota count is still increasing.

Darn, I was hoping that would be a quick fix.  You’ll need to change ‘End current survey’ to ‘None’ and add a survey flow branch to end the survey.

OK, done, thank you! Any idea why it behaves like that? (To know which quotas I need to recode and which ones I don’t).

I don’t know. For a number of other reasons, I almost always use ‘None’ and the survey flow.

OK. And is it important to tick “None” in the Quotas? Or can be define End of survey both in the Survey flow and in the Quotas?

I would tick “None” in the quotas; that way you know exactly what it is doing. 

I see it’s just a question of clarity. Thanks!

I thought your suggestion worked, but it turns out it didn’t. 
The quota keeps being exceeded, despite the implementation, cf. below.

Do you have an idea what’s going wrong, and how to fix it?

​@bixiou,

Did you check ‘Do not increment quotas’ in your End of Survey customization?

Yes. I think I’ve found the solution: when setting the condition, instead of “Is Equal to”, I need to use “contains”. 
It’s weird because I don’t see why the quota is incremented if the condition is not recognized as met, but this seems to solve the bug.