I asked a similar question below but want to know when contingent worker supplement data (1995 and 2005) will be added to IPUMS-CPS. I am developing a research proposal and consider using IPUMS-CPS.
Unfortunately, at this time we do not have a timeline for releasing the Contingent Worker Supplement Data. However, our CPS Team is aware that there is interest in use of the data. I would recommend that you check here periodically and if you have not seen anything related to the CWS in early 2019, feel free to reach out to us again and we will see if there are any updates. We also send out out data release emails periodically, so if you register for an account with IPUMS CPS, you can keep an eye out for a note of the release of the CWS.