Company policy allows employees to take a 15 minute break during each half of their shift. The policy also states that this break cannot be taken in conjunction with your lunch (to essentially extend your lunch period). Would it be considered appropriate to take the break 30 minutes before lunch or is that too close? In this situation the employee will typically run and grab their lunch from a local food establishment so they have food for their actual lunch period.
In my opinion (and were I your manager) I would see what you described as being in conjunction with your lunch. You are in fact extending your lunch period, you're just not doing it contiguously. Moreover, your break would be taken for the express purpose of getting your lunch.
Also as a manager, that would leave a bad taste in my mouth about the person doing it because it's clearly trying to get around the intent of the policy (which is that you take a break apart from lunch) on a technicality.
But yes, you need to talk to a manager of yours or HR. We can only speculate.