A new teaser for Jessica Jones' third (and final) season was shown during Netflix's June 2019 scheduling video. While it didn't reveal a specific date, the streaming service's decision to run the video during an announcement of June 2019 debuts appears to signal a June debut.
Take a look, beginning at the 3:36 mark:
The video encompasses Netflix's June 1 - 15 debuts, so it could be speculated Jessica Jones would return in the second half of the month.
The debut date of The Punisher's second season was teased in a similar way by Netflix previously.