Frontier Developments have addressed their player base through a forum post, explaining what the future holds for them and Elite: Dangerous. It outlines smaller updates that will come along and says major updates won't come until late 2020.
Zero major updates until late 2020 sounds a bit egregious at first but it is actually a regular release schedule for many games when it comes to expansions. Elite: Dangerous - Beyond Chapter Four was released about two months ago and a little over a year and a half for the next major content update is to be expected. For example, World of Warcraft has been following a similar release schedule for over a decade.
One important note that the developers mentioned is that the next big update will not be a free one. The content will be paid for and it will apparently be the biggest Elite: Dangerous update up until that point. Holders of the lifetime pass will naturally get the update with no extra charge.
On the other hand, players will not be left without anything to do, despite the lack of major updates coming anytime soon. Regular updates will keep popping up every three to four months and events will be present in between. These events will be refreshed in the upcoming months as Community Goals will see some changes.
Despite Frontier Developments seeing Community Goals as a good tool, they have noticed some players found them to be routine and are looking to shake things up. The frequency of Community Goals will be changed in the future and they will become a bit more integrated into other events.
New scenarios, reputation, reward boosts, new game assets and more will be coming along in the aforementioned events with the goal of making them tie into the game world properly. The goal here is to keep players engaged until the next big thing happens.