Timestretching a track

[sdantonio93]

HI

I have a track with a series of pulses on the track (this is for a university neuroscience project). The pulses are centered at 150hz. The pulses are created by feeding a right ear sine wave at 150hz and a left ear sine wave at 146hz, resulting in a 4hz pulse in the brain. What I'm looking to do is stretch the track and change the pitches as follows:

Right ear 150hz, left ear 146Hz, Pulse 4Hz, duration 5 minutes
Right ear 150hz, left ear 146.5Hz, Pulse 3.5Hz, duration 10 minutes
Right ear 150hz, left ear 147Hz, Pulse 3Hz, duration 15 minutes
Right ear 150hz, left ear 147.5Hz, Pulse 2.5Hz, duration 5 minutes

Ideally what I would like to do is initially hold the 4Hz pulse for 2.5 minutes then gradually change it to 3.5Hz over a period of 2.5minutes. Then hold the 3.5Hz pulse for 7.5 minutes and change the pulse to 3Hz over a 2.5 minute time period.

If I can only do linear ramps of 4hz to 3.5HZ over 5 minutes, then 3.5 to 3Hz over 10 minutes with no holds that will also work.

I'm using Tracktion Waveform 13 pro on a windows 10 machine.

I guess the first question is, is this even possible?
Then, how do I do this?

Thank you
Steven