In cases of fresh/new contracts, my advice to you would be to suggest the contractor obtain a license for a maximum number (exceeding 400). This can be done by paying the prescribed fee applicable for this number bracket. If such contracts are in effect and the contractor is facing this situation, there is a provision under section 28 of the Contract Labour (R&A) Act, 1970 to apply for an amendment of the issued license.
Also, please ensure that your firm, as the Principal Employer (P.E), has a registration certificate for engaging more than 400 contract laborers. If not, you may have to request an amendment of the registration certificate by paying the prescribed fee and submitting an application for amendment to the Labor Office/Assistant Labor Commissioner.
Thank you.