Be thankful for the job you’re outgrowing. It’s the reason you can outgrow it.

The thing you are tired of is what built the capacity to leave it. Six months of early shifts, difficult customers and a manager who taught you to show up on time is exactly why a better job will now take you seriously, and none of that was available to you before you started. Outgrowing something is evidence that it worked.

Before you hand in your notice, write down what it actually gave you. Then leave properly: full notice, no coasting at the end, and a word to whoever took a chance on you.