BAH does not require BA-coded flights to give nTPs as it's pure eligible spend (1 nTP per £ spent) but you won't get any bonus nTPs for the flights.

For the purposes of the OP, as quoted by link2, and outlined by crazy8534 the 80% threshold must be

The BA coded flights for this threshold apply for flights-only. You can still contribute to this threshold with BAH eligible spend nTPs regardless of marketing but the downside with non-BA coded flights within a BAH is that you won't get bonus nTPs.

This is backed up by Cruddite's example of a QR coded flight within a BAH earning zero bonus nTPs but still received full quota of BAH eligible spend nTPs.