The first Autodesk software typically comes out mid-March. the third week of March is usually a good guess. Then the release of software goes into April, usually the second or third week, mostly due to the "packages/bundles" of software that get released. There are a few products that does not apply toward, but Revit and AutoCAD do not fall into that category. That's been happening for about 2 decades now, so everyone just assumes that since their college age children were not born yet the last time this release cycle did not happen, that it's just going to happen as it always has. It will this year as well.
As far as .3.... it will either get released soon or just incorporated into 2019. Most likely, it will be soon and likely it's just a stability release.