Due to delays in the retrofit process, Singapore Airlines (SIA) has postponed the planned launch of its new premium economy class on some major international routes. These include Paris, Frankfurt, New York, Mumbai, Shanghai and Tokyo, and are all served with Airbus A380.

SIA said the new seat class, originally due to launch fleetwide on Aug. 9, has been delayed because A380 modifications are still incomplete. The upgrade process delay has also made the aircraft unavailable.

“We had expected to have seven retrofitted A380s in service by now but, at present, we have [only] three, serving the Sydney, Hong Kong and London routes,” an SIA spokesperson said.

SIA has offered passengers who booked seats as far back as February this year a change to an alternative seat type, along with an onboard-spend voucher of up to $180. Affected customers “will be contacted progressively by Singapore Airlines or travel agents to offer alternative travel arrangements,” it said.

The new $80 million seat retrofit is based on ZIM Flugsitz seats as specified by inflight designer JPA Design Group.

However, the complexity of installing the seats in existing aircraft has apparently taken longer than projected. SIA said it is “working to complete the installation program as quickly as possible,” in a statement on its website. The website also stated that some services will not be able to offer originally scheduled premium economy seats until after February or March 2016.

Premium economy seats that were booked on the airline's Boeing 777-300ER aircraft are not affected by the delays, and are being scheduled as originally planned.