Hi!
If you are just trying to understand which AP transmits on 2.4 or 5 GHz, then you just need to hover any SSID in the sidebar and check its hint, or just review the corresponding column in Discover mode: /help/what-is-discover-mode/
This functionality is available in NetSpot Free.
If you want to predict which AP your clients will connect to in a specific point on a heatmap, you just need to hover that point after the visualization is compiled (SNR or Signal Level) and check the values in the sidebar: the AP having higher values will be the one users will connect to. NetSpot PRO will soon feature sorting by Frequency Band, this option will simplify networks’ management and analysis.