Hostapd uses the same channel as the interface causing possible issues

[alonsovidales]

The other day trying to troubleshoot some connectivity issues in a school we realised that the ElimuPi, ElimuConnect and the 4g router were using 2.4Ghs and channel 6 for all SSIDs, since all the devices are using the same freq and channel and they are close to each other our guess is that they cause interferences.

According to the docu: https://wiki.gentoo.org/wiki/Hostapd

An AP can have multiple SSIDs, making it look like multiple APs, but all will share the same band AND channel.

I this case we only create one SSID but since we use the same physical wlan card I guess that the channel has to be the same, we can only have one per card.