I’m going to be having restorative work done on my front teeth, when should I do teeth whitening?

At least 2 weeks prior. I would recommend going earlier if you'd like to brighten significantly because it may take a few sessions to get to your desired shade. 2 weeks will allow time for your shade to settle & for your dentist to match your new shade. If you have an existing filling in the front teeth that you are looking to have replaced, there may be a time period after whitening that there is a colour difference between the natural tooth structure & filling material, since the filling won't lighten past its original shade.