I cannot imagine that a regional route - particularly one like MNL, where CX is the undisputed premium carrier regardless of what product they put on the route - is a priority for CX to install their new long-haul J class on, not to mention that route frequently has EQV or last-minute swaps regardless. The flight time is less than two hours....

Maybe it will infrequently appear on the route as CX is trying to sweat their fleet a little more...aka, maybe there is a utilization lull as it cycles between long-hauls...but I see zero reason why they would ever "sell" their new long-haul J to MNL.