I don’t want to automate the effect’s various settings, simply to turn it off (“automate a bypass”) for a bit.
Bypass is one of the automation parameters. If you want to automate the bypass you need to add an automation envelope for it. Right-click on an empty part of the audio track and select FX Automation Envelopes | FX Automation. Then select the Bypass parameter and place keyframes on the envelope to turn it on and off.
Alternately you could split the audio event at the point that you want to add the FX and add a “non-realtime effect” to just that section of the clip. You could also isolate that part of the audio on a separate trace and apply the FX to that track.
There are lots of ways to do this but automation is probably the easiest way.
~jr
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