Wireless Hardware is not present after A06 BIOS Update (7737A06.exe)

I have a Dell Inspiron 17 7337 laptop on Windows 8.1. I had a BIOS auto update pop up with the file 7737A06.exe

After my laptop rebooted, it can no longer see my wireless network adapter. Unless I have an Ethernet cable plugged in, no devices show up under Network adapters.

Tried googling this and setting something under Advanced to enabled in BIOS and this didn't work.

Tried going to Dell support and re-installing drivers and nothing has changed

If I run the Intel PROSet / Wireless Tools and run a diagnostic, it fails on the Hardware Test saying "Wireless Hardware is not present"

I also tried seeing if I could roll back the BIOS and the Dell support page suggests going to Drivers and Downloads, selecting Operating System and choosing BIOS under category - there is no BIOS category. You can choose BIOS instead of O/S in that section, but it shows no filter options at all.

Also tried System Restore and it won't work as says likely due to anti-virus so I disable that and it still doesn't work.

At a bit of a loss here.