The blue circle on this galactic map contains the total extent of human spaceflight. Although phase gates permit faster than light travel, the ships which construct new phase gates are limited by the speed of light. The maximum size of transgov space is therefore determined by the number of years humanity has possessed dark matter ion drives.
The red point indicates your current position in the galaxy. You are near the pulsar PSR K1745-2856, just rimward of the globular cluster Djorgovski-2, at the base of the Milky Way's Norma Arm. You have traveled further than any human being in history.
The blue circle will not contact the red point for approximately 20,000 years. (It may help to think of this as four times the length of recorded human history.)
This rules out both rescue by a follow-up mission and self-rescue by Neptune rocket.
The Cicada mission is now effectively a separate civilization. The only possibility of rescue or return lies in whatever phenomena brought the *Cicada* to Proteus.