There are two articles on this site that deal specifically with a Fish in cycle gone wild, But the information also applies to you situation.
What actiaon one should take depend on the actual readings and parameters which the article explains. If you age an ammonia spike you will likely follow it with a Nitrite spike. For nitrite there in no need to change water as we can use a bit of salt which is sodium chloride and the chloride blocks nitrite from enter fish.
Ammonia in water goes into two forms. One is ammonia (NH3) which is very toxic. The other is ammonium (NH4) which is way less harmful especially short term. The article explains is all.
Depending on your parameter and test readings, the article will show you what you need to know and do. Most ammonia levels can be too high for doing anything besides water changes and/or using an ammonia detoxifier.
https://www.fishforums.net/threads/rescuing-a-fish-in-cycle-gone-wild-part-il.433778/
As far as I am concerned anyone who claims we need automatically to do big water changes in reaction to
any reading of ammonia or nitrite is misinformed and what they say should be taken with a grain of salt.
I have been helping members on this site dealing with this sort of issues for a number of years. However, I will not do in a thread like this one. I will work one on one with folks via site PMs, Email or voice over the phone. I do not text however. I have one rule for working with folks and I always suggest it.
On sites like this one it is easy to get advice from different sources which is not the same from each person. That often confuses people trying to solve a problem. So I will always suggest that one with issues pick one voice only and lisen to it. That way one of two things will happen. That preson will know what they are talking about and you will fix the issue. On the other hand, if the advice you get is bad and it doesn't help, you will have leaned whose advice to ignore in the future.
Just as an FYI as to my experience- I have been keeping fish going into my 25th year. Over that time I have cycled close to 100 tanks. I usually had to cycle multiple tanks all at the same time and I would do this by setting up a bio-farm and cycling filters. As an FYI- it takes me about 10 days to 2 weeks to get all the filters cycled for 8 tanks holding a total of 220 gals. I do things this way as it is much faster and a whole lot less work.