You can verify Warrant Canary status with this command on your system console

delv txt +short
dig txt +short (this will get you results without validating the DNSSEC is valid)

You would get a response of:
"version=canary1; warrants=0; date=20181202; expires=20190530;"

version= DNS Warrant Canary Version
warrants= number we have been issued
date= YYYYMMDD of when this was issued
expires= YYYYMMDD of when this expires, if expired then canary is dead

Running with +vtrace to validate the RRSIG:
delv txt +vtrace
; fully validated 871 IN TXT "version=canary1; warrants=0; date=20181202; expires=20190530;" 871 IN RRSIG TXT 10 3 86400 20190228000000 20190207000000 34464 QQc3mN0764EHoND2oqkk928zxazB0oYqtjHiS7m3Fu6bgjCsrfnOlZA0 /6aQn6nQHvb3Jez/z6O4Mr3jUUh5zBxVL5HBLqAX15IBUKRVxAcAhAz8 VQoUgCqDJwc/uelFPwzeu82ZR44AWNLObSdrqXuMFEyR26VmlKwlDOul 8Ub2JLR7g88t3BHkv8yP0UrJ2mjw5JjZWF89cYyGgBMgPa9oj/0WNGgk ZPme+HpCtzF7eULUFpveden9VmFijpQppR47qMdHo6ZPhqjEnT5qyBFO qX9XWiHz8hJ04XCLq3CXpE6198t35yVV+hrlPmvdcHRtljYHw34b0l95 IOrzyw==

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