LOL! Yep, it will be that.
Just remember everybody is different!
For me, a couple of things stand out.
Trucks and buses were just plain loud to the point it took me about six months to get used to them.
Speech was the easy part for me. Took me about a day to get that down. Heck, I could use the phone after a day or so. Listening to the TV wasn't too bad even though I did have to get used to the "fast and furious" conversations they sometimes have. Radio was quite good especially talk show. Music was pretty good after a couple of days. I say it took about a week or two to get used to the difference of a CI over a HA.
On the other hand, it took me several days to get the environmental sounds down. That is because things sound differently, one has to classify what one hears. It can take a while. I think it took about four days to get the most common sounds down.
The water faucet! I couldn't believe how high it sounded.
The public toilets flushing so loud that I cringed.
Hearing around "corners" and behind me like when my kid said "shucks" when he didn't get his way on something.