If it doesn't reach a decent level after that, well then APAC was always doomed. And the servers will probably be shutdown.
If they merge Dalborra, Gav and Master D the population will be more than decent. Dalborra isn't all that bad atm but would greatly benefit from the addition of both the other 2 APAC server populations. I doubt they would have to worry about APAC server population again if they go through with a merge of all three.