Korean Air is boosting its route between Seoul and Hong Kong with the addition of a fifth daily flight starting October 28.

The new flight, operating under the codes KE611 and KE612, has been scheduled in order to give passengers the entire day in Seoul as well as connecting more efficiently to transfer flights at Incheon Airport.

That being said, this is a late night flight travelling in both directions. Flights depart Seoul at 21:45 and arrive in Hong Kong just after midnight at 00:40, while the return leg flies out of Hong Kong at 02:05 and arrives back at Seoul at 06:20.

While the introduction of a fifth daily service will no doubt be welcome by travellers, there is some bad news regarding the seats they will be able to book on this flight.

Korean Air currently flies three different aircraft on this route – its 777-300ER operates two of the daily services while its 747-8i and 787-9 Dreamliner each operate one.

These all offer good, fully flat business class seats – the 777-300ER and 747-8i even offer first class Kosmo Suites and the 787-9 has six Sleeper seats, which Korean Air bills as first class.

This new daily offering, however, will be flown by the airline’s single-aisle 737-900ER. Business class on these aircraft comprises just 12 Prestige Seats, which don’t even recline to a lie-flat position, let alone fully flat – a definite issue on such a late-night flight.

Further adding to the range of options available to travellers on the route, rival Korean carrier Asiana Airlines plans to upgauge to its Airbus A380 superjumbo on one of its two daily services between Seoul and Hong Kong on the same day Korean Air is adding its new daily flight. This aircraft not only features the airline’s fully flat Business Smartium product, but also its enclosed First Suites.

Korean Air is undergoing a few changes with its Hong Kong services on October 28. Along with its fifth daily service from Seoul, October 28 will also see the end of Korean Air’s non-stop connection between Hong Kong and Busan.