can't go into ship mode outside of an event handler

Using code from the npm13xx_one_button sample, going into ship mode from event_callback(const struct device *dev, struct gpio_callback *cb, uint32_t pins) works fine on a button release with the following function call:

regulator_parent_ship_mode(regulators)            //static const struct device *regulators = NPM13XX_DEVICE(regulators);
However, I need to go into ship mode after a long button press without a release. So I set a timer on the button press, and call that same function from my timer handler but the device doesn't go into ship mode. I suspect that it's because the parent is only 'known' inside the handler. 
is there a way to make the parent available outside the handler? or is there another way to go into ship mode without a parent (since my board only seems to have one regulator). 
Thank you.
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