It's married segment availability on paid tickets. There have been several examples of this posted on here over the past few months, for DFW in particular, where DFW-XXX is J0 but if you're connecting the flight is J7. On 6/5, the early DFW-HNL is J7 while the later flight in question is J0. AA is basically restricting DFW originating pax that want to buy J to the early flight. However if you're not originating in DFW then the flight is J7, below I searched RDU-HNL for example.