Wifi 5 GHz not working on OSX Yosemite 10.10.5

[scrovy]

Recently, the wireless adapter had issues reconnecting when waking up from sleep mode on my MacBook Pro (Retina 13", Late 2012). I tried solutions on the internet of deleting the configuration files on /Library/Preferences/SystemConfiguration, resetting SMC, and creating new location, all without success. Also resetting the router does not work. Needless to say, everything works perfect on my iPhone, so I'm sure that the problem is with this MacBook, or otherwise its interaction with the router. Now, I can neither find the SSID or connect manually, when I configure the router to 5 GHz. When I configure it to 2.4 GHz everything works fine. On the router side, the SSID is the same for both bands, and you can either select 2.4GHz or 5GHz, not both at the same time. The protocol is configured to be selected automatically (802.11b/g/n), as is channel and bandwidth.

According to the App store, Security update 2017-003 version 10.10.5 was installed one and a half weeks ago, so I suppose the problem came with this update. I have Time Machine disabled, so that I cannot restore my computer to a previous state, unfortunately. Using the Wireless Diagnostics app, scan fails to find networks on the 5GHz bands. Also, when I select 2.4GHz and connect, this stats are shown:

IP Address, Router, Internet: Reachable (everything fine)
Security: WPA2 Personal
BSSID: the mac address of the router
Channel: 6 (2.4 GHz, 20 MHz)
Country Code: CN
RSSI: -44 dBm
Noise: -88 dBm (this makes 44 dB signal-to-noise ratio, perfectly fine)
Tx rate: 117 Mbps
PHY mode: 802.11n
MCS Index: 15

Anyone with experience herein?

EDIT: The supported channels as shown on system report are 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 149, 153, 157, 161, 165, whereas my router only supports channels in the range 36-144 or so. I suppose this is a new change, since some weeks ago I could connect with no problems. Anyone knows how to change the range in Mac OSX?

EDIT2: A router of an obscure neighbour with country code CN is causing this mismatch in channels. Of course I don't know who that person might be, so I needed an intrinsic solution with my own Macbook and router.

 

[scrovy]

Update: I used a patched driver version of AirPortBrcm4360 that you can find on https://www.blix.com/eirik/annoying-80211d-protocol. Make a copy of /System/Library/Extensions/IO80211Family.kext to e.g. your desktop, replace the patched binary inside the copied kext, in IO80211Family.kext/Contents/PlugIns/AirPortBrcm4360.kext/Contents/MacOS/AirPortBrcm4360 to be precise. Then install this modded kernel extension using the Kext Utility (google it). It turns out that this mod was incompatible with my kernel, but in one way or another, the OS falls back to the Brcm4331 driver and miraculously the EU country code is chosen (where I live), with the UNII-1 band available (channels 36-48). This band overlaps with my router. Don't ask me why, but it worked this way (hopefully...) Now I just set the router to one of the supported channels and it works.