Updating Firmware Over WiFi

[Android Central Question]

I'm an Australian Citizen and I bought a S6 Active over the internet almost two years ago. It's served me well despite not being wired to work that well over our 4G Networks. I shorted the Micro USB about a year ago now after arrogantly plugging it in after dropping it in the pool on holiday, but it's been fine up until now since I can transfer files over Bluetooth and charge it wirelessly.
But now everything started to slow down and I can't figure out a way to update the firmware since to do it over 4G you need to be in America and every other method I've read up on requires a USB port.
Is there a fix for my problem or am I going to be stuck with Jellybean for the rest of my days?
Thanks,
Eldon.

 

[belodion]

I should have thought that the S6A would be running Lollipop if never updated, but anyway, is there an objection to having the USB port replaced? Bear in mind however that the water and the charging while wet may have done damage, some of which may be ongoing.