Hi,
You can modulate the parameter by using the Release time from a Function that's set to a envelope mode or from a Envelope, as the release time is starting when a key is released.
The parameters initial setting, the modulation amount and it's polarity, the sustain points and in example a functions set points and curves will all have and impact on the modulation, so you can have full control over the parameters value at any time - especially when using Functions in envelope mode.