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.