I see that the lease is for 6 months only through northern winter and expires in Feb 24 when Cathays schedule will start ramp up again to ifs normal 6 flights per day into LHR and to 100% of its schedule.
Currently and well ahead of its 70% 2023 plan LHR is being served 4 times daily from HKG
It seems a good move to get income from otherwise temperately unused slots at LHR as these are scarce and derive good income. These short term leases are very much the norm at LHR.