The 4011 is a peculiar device, see:
You need to use the "old" wireless driver to have both radios (2.4 GHz and 5 GHz) working, the "new" wifi driver ( wifi-qcom-ac) will only work with the 5 GHz radio.
If you remain with the same "old" wireless driver you don't need to change anything if you upgrade to 7.x, the upgrade process will normally keep your current configuration work as before.
If I were you I would do this in two steps.
First update to latest v6 version.
See that everything works as you wish (or post if you have issues).
Then think a bit about what advantages (if any) v7 might bring to your setup.
If none, you can stay on v6 for the moment.