>>13049699The launch is scheduled for October, but the launch contract specifies that JWST needs to arrive at the launch site 62 days before launch.
To get there it needs to be trucked from the production site to Long Beach, loaded onto a boat and taken though the Panama canal. That packaging and shipping takes a long time, about a month unless someone blockades the Panama canal.
So what they're really looking at isn't 6 months, they have until the end of June to get JWST ready for launch.
The JWST status page has not been updated so far this year
https://jwst.nasa.gov/content/status/index.html 
