After a week of playing Kingdom Hearts Unchained χ since it came out in Australia, I caught up to the mission cap and I've been trying to figure out how many missions are total in the game. In the English version, it's 350 missions while the Japanese version has 475; and the story isn't done yet. 

Does anyone know how many Kingdom Hearts Unchained χ there will be in total to finish the story?

Alternatively, does anyone know if Kingdom Hearts χ[chi] (browser game) is done in Japan storywise and if so, how many missions total does it have? 

I'm just wondering how long I'll be playing this oddly addicting game for

After a week of playing Kingdom Hearts Unchained χ since it came out in Australia, I caught up to the mission cap and I've been trying to figure out how many missions are total in the game. In the English version, it's 350 missions while the Japanese version has 475; and the story isn't done yet. 

Does anyone know how many Kingdom Hearts Unchained χ there will be in total to finish the story?

Alternatively, does anyone know if Kingdom Hearts χ[chi] (browser game) is done in Japan storywise and if so, how many missions total does it have? 

I'm just wondering how long I'll be playing this oddly addicting game for

No one will know until it's done. KH X will be done in Aug. but it isn't in the mission format that KH UX is in, so you can't really compare it.

KHX doesn't have missions, it has chapters, and they are rearranged and overall different from Unchained. The basic plot is the same, though.

Khux in japan actually got to 500 in april and most likely has more now, and that isn't quite as far as KHX has reached. also, I don't think KHUx is going to end where KHX does it might go on a little further. It might not necessarily add any relevant plot, but they will most likely keep adding stuff so people can continue playing.

KHX and KH UX both share the same (or similar) story but execute their gameplay in different formats. KHX does things in a much more straightforward chapter method, where each task just sort of counts as a chapter. You can kind of think of it like how things are done in Unchained, only where once a mission was done you don't do a little victory pose and head back to the mission select screen, you just get your next objective and keep going forward while you're still in that world. Once you've reached the end of that update you're told that "the rest of the story can not be told yet" and that takes you back towards the menu screen. KH UX's system is admittedly less straightforward but a lot more robust with it's whole mission-centric style, which is actually pretty consistent for those who are still familiar with 358/2 Days' structure. In any case, both are progressing their stories and gameplay in different ways, so it's really hard to compare them like that unless they just so happen to be issuing updates to each world's story in similar chunks and pieces. However, since no one is quite "caught up" with KHX yet (though I imagine KH UX in Japan is pretty close by now) it's really hard to compare story updates in that kind of matter as well. Point is, if you want to try and compare between the pacing of KHX and KH UX, you'd probably be better off comparing each world's story content in KH UX with each update and compare that to somebody's letsplay videos of KHX, such as Everglow's. You won't have a proper number count of missions in between, but you will be able to compare them based on how much of the story is told at each time.