It is possible to create a filled zone connected to a specific net but not including the already routed tracks?
Explaining the reason:
Sometimes you create a GND filled zone but, some IC works better with some pin connected to a specific point of the board. For example, some ADC needs the ref pin (wich is also the GND NET, the most of the time) connected close to the measured point to avoid EMI and propagation interference fluind together with the reference signal.
I know the some professional softwares (as Altium) allow this configuration.