Yes as the titre implies, some people are starting to have doubts about whether the 5th addition to Alpha and Omega is actually going to be released. Well I know it's going to come out (when I don't know) but here are some possible reasons:
One reason could be that the company wants to keep things secretive to surprise the audience. Take for instance Nintendo and the game Zelda Wii U(not final name) that's expected to be released this year. They have only posté one real trailer and 4 screenshots from a dit trailer in the four-year development cycle. This shows that they really want to surprise the audience.
Another possible reason could be that the movie could be a full feature film. If anybody saw the behind the scenes from the disc toi would know the first movie took 5 years to complete approximately. The company could actually be taking their time to make the movie as good as possible.
One last reason could be the lack of manpower. As toi most likely know, making an animated movie is harder than an jouer la comédie movie because everything has to come from the mind of someone to the big (or small) screen. Although this reason could be a bit lax and hard-to-believe putting into considering the fourth movie, the possibilities are endless.
So there toi have it. Everytime toi doubt the films release, just think about these reasons.