Comment 15 for bug 1713348

> If you have a kernel image package say linux-image-4.9.0-test,
> you may have have a header package linux-headers-4.9.0
> (without the '-test' part) or some other similarly named package, right?

No.
The related headers package would only be linux-headers-4.9.0-test

Example (edited):
doug@s15:~/temp$ dpkg -l | grep "\-4\.9\.0"
ii linux-headers-4.9.0 4.9.0-277
ii linux-headers-4.9.0-stock 4.9.0-stock-165
ii linux-headers-4.9.0-test 4.9.0-test-275
ii linux-headers-4.9.0-test-test 4.9.0-test-test-276
ii linux-image-4.9.0 4.9.0-277
ii linux-image-4.9.0-stock 4.9.0-stock-165
ii linux-image-4.9.0-test 4.9.0-test-275
ii linux-image-4.9.0-test-test 4.9.0-test-test-276