if you reason for late moving to regional area is reasonable, it shouldn't be a problem. Co asked you to explain is giving your opportunity, if not they could reject your application without asking reasons. One of my friend have the similar situation like you, he applied 887 visa this year and still waiting ,he consulted some agencies , they said it is not big issues if the reason is reasonable. So don't worry . Wish you get your grant soon. AND if possible when you get your application results, could you please share with us ?