What happens to the Netflix remaining credit?

I would like to buy a 15 euro Netflix prepaid card and thus purchase the standard subscription for 11.99 euro. What happens to the remaining credit? I read that you can use it for a few more days until it is completely empty, but the answers were always very old. Is that still the case?

Yes, then you have a few more days of Netflix.

That's great.

So it is used automatically and with 3 euro, that would be 1/5 month.