Apple replaces 2019-002 Security Updates for 10.13 and 10.12. BridgeOS updates also show as new. – Mr. Macintosh

Security Updates for both 10.13. and 10.12 have been replaced with new builds. The original 10.13 High Sierra 2019-002 build # was 17G6029, now it’s 17G6030

Source: Apple replaces 2019-002 Security Updates for 10.13 and 10.12. BridgeOS updates also show as new. – Mr. Macintosh