As you said yourself this functionality isn't supported out of the box by the Scheduler control. Unfortunately due to the complexity of the resizing logic, implementing this as a workaround or with custom outside code is going to be cumbersome and hacky, and might result in erroneous behavior in some cases.
We do however plan to introduce a similar behavior integrated into the control in some of our future releases. You can also log this as a feature request in our public portal, so that other people can vote on it in order to increase its priority:
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