5GHz AP configured for ch120, lands on ch116: normal/DFS?

Installing and Using OpenWrt
1

This may be a newbie question. Not a problem as far as I can tell just something that I wasn't expecting.

I've installed the latest 23.05-SNAPSHOT (r23222-02a37dee1b) on a Netgear WAX206. The 5GHz radio is configured for channel 120:

config wifi-device 'radio1'
	option type 'mac80211'
	option path '1a143000.pcie/pci0000:00/0000:00:00.0/0000:01:00.0'
	option channel '120'
	option band '5g'
	option htmode 'HE40'
	option cell_density '0'
	option country 'US'
	option txpower '10'

and is running a single, AP, network, which however (as of the latest reboot anyway) landed on channel 116:

# iwinfo 
...
wl1-ap0   ESSID: "..."
          Access Point: nn:nn:nn:nn:nn:nn
          Mode: Master  Channel: 116 (5.580 GHz)  HT Mode: HE40
          Center Channel 1: 118 2: unknown
          Tx-Power: 10 dBm  Link Quality: 57/70
          Signal: -53 dBm  Noise: unknown
          Bit Rate: 487.4 MBit/s
          Encryption: WPA3 SAE (CCMP)
          Type: nl80211  HW Mode(s): 802.11ac/ax/n
          Hardware: 14C3:7915 14C3:7915 [MediaTek MT7915E]
          TX power offset: none
          Frequency offset: none
          Supports VAPs: yes  PHY name: wl1

Previously, still on the 23.05 code (previous 23.05 snapshot imagebuilder) the AP was landing on 120 exactly. Both then and now the AP works normally, this just made me curious.

Is this normal, maybe a side effect of radar detection?

2

ok

3

Right, at 40MHz width it's an overlapping channel. I just wanted to confirm that the center frequency being different than the specified one is "normal".