Nothing out of the ordinary to check. It will still behave like any ethernet interface you have.
It depends on what RouterOS version you are running and under which RouterOS version the configuration has last been reset to defaults.
The newest versions have interface lists where you can just add your interface to a WAN list and everything is fine. But that is a default
configuration change that will not be implemented by merely updating the software, you will need to first update the software and THEN do
a reset to defaults. (unless you have done that before)
In this case you would have to re-build your configuration from scratch.
If this is a lot of work or a matter of a couple of inputs (passwords, mainly) and mouseclicks, depends on your actual configuration.
Note that this change does not make everything work automatically, it just makes it easier to do. You can just as well do the
required changes in the different screens. There is not that much to do, you only have to be careful doing it or else you will be
back complaining that the CPU is fully loaded, the internetlink is saturated, and you cannot find what is wrong.
(at that time you have been victim of someone using your router to DDoS some bank)
Ok but you already are running the newest 6.41.1 version so that change already is effective. You have a bridge interface with all ports in it, instead of only ether2 and ether6 which were master-ports before. The reset will only bring you a new (easier to modify) firewall.
The new firewall uses “interface lists” where an interface can be member.
You have a list LAN and a list WAN by default. In your case you only need to move SFP1 from LAN to WAN.
And when you have to run PPPoE over it, you create a PPPoE interface and make that member of WAN.
Much better than to have to modify the interface in the firewall rules.
It also has some fixes for problems with fasttrack combined with VPN.