Everyone knows now that the update scheduled for April is called Memories of Reach. However, some people don’t know that a Forge World remake has already been confirmed for Halo 5. Therefore, I believe it is entirely reasonable to assume that Forge World’s addition will coincide with the release of the Reach update. Just food for thought 
Here is the link to the confirmation if you haven’t seen it : https://twitter.com/pardontomfrench/status/690358277427851268
I tried posting this in another thread about that update but it was mostly ignored -.-
So pumped though!