I don’t think we’ve been able to identify the source(s) of the advice to change learn-ahead to 0 (discussed a couple times in other threads). It still strikes me as odd advice, and it seems contrary to what most users would want.
I would completely guess (based on my not entirely reliable memory) that the questions about this feature are about
- 90% of the “I want to see those cards sooner”/increase-your-learn-ahead variety
- 10% of the “I want those cards to wait out the delay, like I had it before”/decrease-your-learn-ahead variety (wherein we find out that the person did change that themselves recently)
Yes, fakenumbers, I know (and I’ll stand corrected if anyone wants to survey the various help venues) – but what’s missing is any sort of a majority that would be better served by changing the default learn-ahead to 0.
The thought process we would want to foster there (and a lot of other places! 
) is “I don’t know what learn ahead limit is, so I shouldn’t touch it.” But for those who second-guess themselves and think they accidentally did anyway, adding a reset-to-default loop 
, like we have in Deck Options, would be a more direct solution.
It seems like there are a lot of recommendations that could help that user –
- Bury those cards for tomorrow.
- Stop answering them and come back later today (or in 10 minutes).
- Accept the fact that flipping through those last few cards a few times before graduating them might have some benefit.
- “Great, you got them right, so graduate them to Review.”