The Qualcomm Snapdragon 835-powered Samsung Galaxy Tab S4 has been around for just six months, it seems that its successor is already in the works and could hit the market in just a few months. The leaked renders show "April 5" on this tablet's display, so this might just be the launch date of the Galaxy Tab S5e.
https://www.notebookcheck.net/Samsung-Galaxy-Tab-S5e-renders-surface-online.407821.0.html