The Half Yearly Labour Return under Contract Labour Act was applicable in two forms
1) CL (R&A) Act, 1970 & (Contract in establishment which comes under state govt jurisdiction (either govt or private establishment).
2) CL (R&A) Central Rules, 1971, Central Rules (Contract in establishment which comes under Central govt jurisdiction (either govt or private establishment).
The Forms, documents and Returns are same under CL (R&A) Act, 1970 but in Central Rules 1971 Act, Form XXIV (Return by the contractor) and and Form XXV (Annual Return by the PE) have been omitted vide notification dated 27th Dec. 2017.
However, where CL (R&A) Central Rules, 1971 is applicable we need to file a Unified Annual Return online on the Shram Suvidha Portal of the Central Govt.
Please find attached the Notification for your ready reference.
The Half Yearly Return has not omitted / deleted under the Act. I have just filled many returns under the Act, even for my Delhi units as well.
However, under the Central Rules, 1971 various returns have been merged. Now you need to file annual Return (for Edning Dec. every year) in Shram Suvidha Portal. Detail of the same has been provided in my above article.
Hope the above will clear the doubts. Seniors can throw more light or correct me if I am wrong.