Deviating every once in a while from 1:1 dub:sub matchup is not even close to an obstacle to language learning. In fact, if anything, you hear and read two different ways to express the same thing at once.
If you depend on 1:1 matchup, I'm not sure you were consuming either dubs nor subs in a way that's all that productive to language learning. Consider relaxing and getting used to fuzzier comprehension which is necessary for transcending to conversational speed+slang.
Also, I recommend graduating to reading books ASAP to avoid languishing in the limbo of Netflix for language learning.
