Quick suggestion, you can you PATINDEX to validate Email as well as to get the Birth Year from the email address.

select dob, adj.YEAR_OF_BIRTH, email, IsValidEmail

from

(

Select cast('20160101' as datetime) as dob, 'abc16@123.com' as email union all

Select cast('20160103' as datetime) as dob, 'abc1@abc.com' as email union all

Select cast('20060204' as datetime) as dob, 'abc06@abc123.com' as email union all

Select cast('20260101' as datetime) as dob, 'abc06xy.com' as email

) A

CROSS APPLY

(

Select Right(DATEPART(yy, dob),2) as YEAR_OF_BIRTH

, PATINDEX('%'+ Right(DATEPART(yy, dob),2) +'%' , LEFT(email, PATINDEX('%[A-Z0-9-]@[A-Z0-9-]%', email))) as IsValidEmail

) adj

--- uncomment this line to get the valid email list

-- Where Adj.IsValidEmail > 0