Something that MikroTik forgot to write in changelog that is more important than everything else:
If you had set a country and use frequency mode superchannel, updating to 6.43.8 will set regulatory domain.
What does this mean? If you don’t use frequencies in default scanlist, you are going to lose stations.
Set country to no_country_set before upgrading.
P.S. Thank you MikroTik, instead of TDMA REAL improvements or a new Dude, a present that is a pain in the a*s.
This can’t be real!
Odesláno z mého XT1635-02 pomocí Tapatalk
Yes, this is real. 
omg … where are you going MikroTik … highway to hell
true… true
thanks for heads up… it would really suck to upgrade now before Christmas to this version and break everything
I was going to believe the OP due to his credentials at the bottom of the post but then I saw he was from Italy, and had second thoughts, probably steering his ferrari with his left foot while checking out his WINBOX connection with his Iphone 10 in one hand and drinking wine out of the bottle in the other hand 
Just kidding, just would love to be in Italy with such minor problems. Merry Christmas or whatever holiday you take part in this time of the year!
Thanks for the heads up!
You call it a minor problem? Probably you aren’t using MikroTik for wireless
Well I do have two CapACs, but I am holding off upgrading until mikrotik responds. Thats why I said Thanks!!!
I fear they are already into the schnapps because they have not responded.
Although Normis should not be in his temporary red shelter (I mean car) intoxicated.
You can always remove country before update, I’m not worried about this decision, but at least it should be written somewhere in changelog: “Disabled superchannel for countries, only regulatory domain for them”.
I am very unfancy with wireless with only two capACs I do not even use capsman.
Also each one has
wlan1 = 2.4ghz for smart devices
wlan2 = 5AC for a. home wifi and b. (virtual) VWLAN for guest wifi
In both 2ghz cases on vlan
In both virtual VWLAN cases on vlan
Not sure if upgrade will affect them as I have no idea what superchannel is??
Canada has limitations on 2.4ghz for example. My AC is using Ceee 20/40/80
It’s Frequency Mode in wlan settings, you can upgrade without problems because you don’t use superchannel for Wi-Fi (phones and PCs won’t connect).
You’re using regulatory domain, I’m 99% sure.
You would have problems after upgrading if you have antennas on towers connected to other antennas, no need to worry for indoor APs.
Using “country” means you want to folow regulatory domain restrictions.
Using Superchannel is exactly the opposite.
Why would you want both at the same time? “Country” setting was always meant to limit your frequencies and power, to follow country regulations (law).