How CNAME's interact with A/CNAME and AAAA/CNAME pools
It is possible to make this configuration:
A/CNAME Directional Pool
Pool Name: Pool1.domain.com.
Pool1.domain.com IN CNAME atarget.domain.com.
AAAA/CNAME Directional Pool
Pool Name: Pool1.domain.com.
Pool1.domain.com IN CNAME aaaatarget.domain.com.
If you query for the "A" record, our resolver will see both CNAME's as acceptable, but it will only serve one.
It does not favor the CNAME in the A/CNAME pool for A queries. It does not favor the CNAME in the AAAA/CNAME for AAAA queries.
If A/CNAME Directional Pool
Pool Name: Pool1.domain.com.
Pool1.domain.com IN A 1.2.3.4
AAAA/CNAME Directional Pool
Pool Name: Pool1.domain.com.
Pool1.domain.com IN CNAME aaaatarget.domain.com.
Even here an "A" query can be answered by the CNAME because the CNAME is a valid answer for a CNAME query.