Training is more than 3 years, definitely not 18 months as they say, so you can definitely except a delay of at least a year and half total during the training phases.
Alpha is a subsidiary of air arabia true but there is no contract between you and air arabia upon starting your training so eventhough you spend more than 200000 USD(including living expenses+ training fees) in 3 years, there is nothing to guarantee that you will get paid when you start flying. They can and will exploit you since the MPL is not valid up until you reach 1500hrs and you pass your final check, so basically you can't leave anywhere. If you try to speak with air arabia management they will tell you " there is nothing we can do, if you don't like it just leave" and can you really leave after you invested that much?
As one of the guys in his post said is true, now they are not paying a salary for their cadets until they are released which might take 3 months or even more or even maybe they just wont pay you till you finish your 1500 hrs. We all hope that things will change for the better though.
I am not telling you not to enrol in the program, I am just stating how things actually are so that you get your facts straight. At the end of the day, air arabia is liable to offer you 1500hrs, but the only question is are you willing to ride that train?