AppleCare stays with the device, so there is no pressing need to have that information corrected. If you need to service that Mac, it will show that expiration date:
- You can go directly to our Check Coverage page. Enter your serial number to see the available service options.
About the purchase date or expiration date for your AppleCare agreement - Apple Support
The only thing you can do is correct the purchase date, if it needs to be corrected. You must contact Apple to do that: To update your purchase date, send Apple your proof of purchase - Apple Support
And will apple lock my device?
No. Apple doesn't do that. This assumes the Mac was not already "activated" by someone else though; in other words a previous owner.