I been thinking that but dealer I bought from has easy and long return policy, so that you can return the machine and get your money back but unfortunately exchanging it to another same model is not possible. Obviously I could just get the money back and then rebuy it but the batch they sold for sale price is gone and they are back to list price for it. Also the same thing seems to be on other local shops at the moment. In my opinion list price for this machine is too much and difference to entry level MBP is so small it would be better choice in that case.
Also knowing my luck, I'd probably just get some other problems with the new machine.

In this current one the display is rather nice, I mean no noticeable light leak, even colors across across the screen (just slightly dimmer right bottom corner but that is quite normal), good natural colors, etc... So probably if I'd managed to find perfect battery the screen would be with uneven colors and/or light leak. That is exactly what happened last year with iPads I kept exchanging... Plus the battery in the "good" one lasted only few months and then dropped considerably... So you probably see why I'm trying to find out if my current one is normal, but it seems not many (or any) other here with the new machine see battery health under 100% in theirs, so that definitely worries me a bit.
Anyway, since you mentioned your Air was manufactured in June 2019 (mine is January) I'm interested to hear if there is any difference in hardware, especially T2 chip, camera (which is quite horrible) and battery manufacturer/cell version.
Could you check following? You can find all information without additional programs, by just holding option key down and click Apple logo on the top left corner. Then select the first menu option (system information) where all the components and their information is listed.
1. Camera. Does it say "UVC Camera VendorID_1452 ProductID_34068"? If not, what version is in yours?
Image quality is pretty horrible but I've hear many peoples complaining about the same thing, so it could be more or less "normal" for this model, unless they have changed to better camera in newer production.
2. Controller. Apple T2 chip does it say firmware version "16P5125"? If not, what is it?
This is very interesting because I've heard there might be some problem with internal SSD encryption causing hang up and I was wondering if they have improved chip in newer production?
3. Power. Battery manufacturer and cell version? What does it say for full charge capacity in there? Mine says SMP and cell version 1838, and for charge capacity number vary a lot but it is the same what CoconutBattery says (mostly under 4300mAh at the moment).
This is interesting part since demo models I saw at the local shop with strong batteries all had cell version 1842 even some had much older manufacturing date than mine, and also some had DSY or DNY brand battery, so maybe that one is just better in the begin with.
Also if anyone else could check theirs, it would be interesting to hear if they are the same and what manufacturing date their unit has?
Thanks for all possible comments!