Your sleep schedule sounds alot like mine haha! I enjoy the luxory of sleeping in after being awoken at 5am, then again at 7am. Some of my best lucids happen in that last chunk of sleep. Do you find this as well for you?

Whenever I wake up too early and can't get back to sleep, something that helps me is to incubate the dream I want to lull me back. I've had maybe a handful of lucids that way, though most happen much later. At the very least, it helps me get back to sleep.