You said F2 only gives a few options? Could you try again and see if this option appears?
1-Immediately after powering on hold/tap the Esc key.
2-When the menu appears, tap F2 for System Diagnostics.
3-In the list of items will be BIOS Management.Use the arrow key to move down & highlight it.Press Enter key.
4-You should now have a Rollback BIOS option.Use arrow key again to highlight and press Enter key.