@TaylorFusion 

Hey

The channels on 5ghz that are DFS (basically anything not 36-48) should be fine to run both your APs on, as the airspace will be clean and only your APs there.. its perfect :)

Each channel on 5ghz is 20mhz wide, so when you set this for a 80mhz channel width on 149..  you basically told it to use  channels  149   153   157  and 161

This picture below might explain that.  the top row of channels (149 153 etc) are 20 mhz and there are 5 of them.   The next row is 40 mhz and there is 2x of them, on 80mh\ there is just one channel.. its also known as 155 (the midpoint between 149 and 161, easier to remember)

When you choose 149 on 80mhz you are basically saying use 155.  Hope that makes sense!

In relation to the 2.4ghz.. that's a different one tbh

Each channel is only 5mhz wide.. therefore selecting say  channel 1..   this is 22mhz wide and will therefore interfere with channels 2 and 3.  

Channel 6  would interfere with   4  5   7  and 8       channel 11 would interfere with  9  10    12   13  

In short there are only 3 channels you can use.   1  6  and 11   -  everything else will be inteferred in some way.

However.. if you switch on 40mhz channels.  that doubles, therefore 1 and 11 are your only real options.

Hope that makes sense!

@Philbert 

Crystal clear, thanks for everything in this thread