NSF continues to transition from FastLane to Research.gov and has announced that all new proposal submissions will fully transition to Research.gov after Jan 2023.
The detailed announcement from NSF can be found here.
https://fastlane.nsf.gov/fastlane.jsp;jsessionid=7d7a6689ebe3b0c0d1dab49eca24?t=0&idx=0
As of October 24, supplemental funding requests including Career-Life Balance requests can be prepared in Research.gov. Supplemental funding requests can be submitted in Research.gov regardless of the system used (Research.gov, FastLane, or Grants.gov) for proposal submission. FastLane supplemental funding request functionality will remain available in parallel for the preparation and submission of new requests until January 27, 2023.
In addition, the last two proposal types for the Small Business Innovation Research Program (SBIR) and the Small Business Technology Transfer Program (STTR) will be enabled in Research.gov for the fiscal year (FY) 2023 competitions. With all proposal and submission types soon fully supported in Research.gov, the system will be ready for the transition from FastLane for the preparation and submission of all new proposals in late January 2023, when the Proposal and Award Policies and Procedures Guide (PAPPG) (NSF 23-1) is effective.
The last day to submit new proposals in FastLane is January 27, 2023