Variable length timer match outputs on AVR?
You can indeed. You simply change the OCRxx register value that corresponds to your match interrupt.

The only thing to be careful of when doing this is that your interrupt is as short as possible, and that you change the OCRxx value as soon as possible within the handler.

If your interrupt takes to long to run, such that your new OCRxx value is matched before the current handler finishes, you will miss an interrupt.