They are waiting on CAD to sign off on new 777/747 conversion courses. With the latest NTC for transfers from 777 to 747, and 777 to Airbus, there will be a follow on one from 747 to 777/Airbus (for HKG based crew only).
The new course will be a "short" course from 777 to 747, and will enable a 2 week short course from 747 back to 777 if done within 4 years of leaving the 777 (the 777 rating will still be valid, recency just needs to be regained). They can then rotate pilots through the 747 efficiently. Significant cost savings are anticipated through reduction in EFP on the 777.
The 777/A330 will be used to train new DEFOs, 777/A350 new SOs. Pilots of all ranks will be moved off the 777 to the 747/Airbus (NTC or promotion).
This will be a significant cost saving measure as the pilots who join come from the 747 have lower annual flying hours and can be used more productively than 777 pilots sitting at 900 hours. EFP will reduce as a result of the anticipated strong uptake of the 777 positions from the senior 747 pilots with more CNs coming from the 747 than being transferred back due to the current excess on the 747.