RouterOS version 6.43.1 has been released in public "stable" channel!
Before an upgrade:
1) Remember to make backup/export files before an upgrade and save them on another storage device;
2) Make sure the device will not lose power during upgrade process;
3) Device has enough free storage space for all RouterOS packages to be downloaded.
What's new in 6.43.1 (2018-Sep-17 06:53):
Changes in this release:

 crs317 - fixed packet forwarding on bonded interfaces without hardware offloading;

 defconf - properly clear global variables when generating default configuration after RouterOS upgrade;

 dhcpv6-client - log only failed pool additions;

 hotspot - properly update dynamic "walled-garden" entries when changing "dst-host";

 ike2 - fixed rare authentication and encryption key mismatches after rekey with PFS enabled;

 lte - fixed LTE interface not working properly after reboot on RBSXTLTE3-7;

 rb3011 - added IPsec hardware acceleration support;

 routerboard - fixed memory tester reporting false errors on IPQ4018 devices ("/system routerboard upgrade" required);

 sniffer - made "connection", "host", "packet" and "protocol" sections read-only;

 switch - fixed port mirroring on devices that do not support CPU Flow Control;

 upnp - improved UPnP service stability when handling HTTP requests;

 webfig - allow to change user name when creating a new system user (introduced in v6.43);

 webfig - fixed time interval settings not applied properly under "IP/Kid Control/Kids" menu;

 winbox - added "allow-dual-stack-queue" setting to "IP/DHCP Server/Leases" menu;

 winbox - added "allow-dual-stack-queue" setting to "IPv6/DHCPv6 Server/Bindings" menu;

 winbox - fixed corrupt user database after specifying allowed address range (introduced in v6.43);

 winbox - make bridge port "untrusted" by default when creating new port;

 winbox - show "IP/Cloud" menu on CHR;

 winbox - show "System/RouterBOARD/Mode Button" on devices that have such feature;

 wireless - removed "czech republic 5.8" regulatory domain information as it overlaps with "ETSI 5.7-5.8";