If even the most remote possibility of this exists, be proactive about it starting today. Get a new number and start advertising it immediately. Keep the old number as your line 2 and in the rollover sequence. Get magnets with your new number and be sure to include one with every order. Boxtop menus with new number. Change the phone number on your website. Soon enough google will start showing the new number and most of your customers will have menus and magnets with your new number and your old number will account for less and less of your sales. In today’s day and age, no one memorizes numbers, they just store them to their phone. My guess is there are as many people that google their favorite pizza shop every time they want to order as there are ones that save that pizza shops number to their phone.