If Home Assistant is offline at sunset or 07:30, the automation won’t be able to trigger at the scheduled time. When Home Assistant is back online later, it will wait until the following day to trigger at the scheduled times.
The usual way to mitigate this potential failure scenario is to include a trigger for the startup event along with appropriate conditions to determine what, if anything, should be done upon startup.
The following is an example of the technique. It’s an old example but it demonstrates the evolution of a simple but failure-prone automation into a robust, failure-resistant automation.