There have been some advertisements regarding various rail mega projects which will link the remotest borders by rail.
Here we look at one such project which may be completed relatively quickly.
The present railhead for Aizawl (and the whole of Mizoram) is Bhairabi, on a branch from Katakhai Jn which is between Badarpur junction and Silchar. This was opened over a decade ago. As was the general practice, the station of Bhairabi was built just over the border between Assam and Mizoram. The MG line was converted to BG in 2016 as part of the extension further into Mizoram.

Bhairabi in metre gauge days.

Bhairabi at the time of conversion to BG.
For an overview of this project, see this (in Hindi with some English subtitles): https://www.youtube.com/watch?v=Hi9mq7gBiSA&ab_channel=FactsMarketGLP
The line is to extend 50.5 km to Sairang, which is about 21 km short of the centre of Aizawl. It is not expected to be extended to Aizawl, due to steep gradients as well as land acquisition problems.
Here is the list of stations according to the RBS tables:

The link to the “rest of India” is Badarpur, so we also give the stations between Badarpur and Bhairabi.:

In 1947, the terminus was at Lalaghat near the present station of Lalabazar.
Note the district HQ of Hailakandi. This was part of Sylhet district which, along with Karimganj sub-division, remained in India while the rest of the district went to East Pakistan.
Let us see if there will be an Aizawl Rajdhani.
You can trace the path of the new line from Bhairabi on this map:
Update: No passenger trains have started running at the time of writing (Sep 2022). Some months earlier there were clashes between the security forces of Assam and Mizoram. The present target date for completion is Nov 2023. This is strange, considering that the stations have already been entered into the RBS database.