company harrasment for resignation if not transfer order to another state

Sir
behalf of my union members i would like to clarify and want some solution for ongoing harassment from company
we are working from last 26 years designation as computer operator and yard supervisors. in Buffer CFS (container freight station) in navi mumbai established by JNPT Port also who is principal owner of CFS.
JNPT port announce tender to run CFS for 20 year period for contract and in their work order its clearly mentioned even if the contractor changed workers will remain same and next new contractor will have to continue them until their retirement.
thus since sept 97 we are serving there and 3 contractors were changed
1st contractor 97 to 2004, 2nd 2004 to 2005 and 3rd 2006 to till date.
for last 26 years all workers are same excluding management staff currently total 429 local workers are there in our firm
now from last 3 years this contractor is harassing us to resign from service and when we denied and file complaint at ALC assistant labour commissioner at Mumbai they issue us transfer order letter in which transfer to another state from current location Nhava sheva navi mumbai to gujarat even if there is no transfer clause mention in our 3 years agreement also no appointment letter provided by current contractor while taking this contract we want to ask that can we challenge this transfer order in court or ALC ? and what is our rights to defend this transfer order please suggest.

First of all, the work on which that you are engaged seems to be perennial in nature and the principal employer is answerable for keeping contract workmen in such jobs.

Second, there have been changes in the contractor but the workers remained the same. This would make the contract sham and just a camouflage arrangement. This should be challenged.

Third, continuously employing workmen as contract workmen is an unfair practice under Industrial Disputes Act.

Fourth, though transfer as a service condition is accepted as managerial prerogative, the same cannot be exercised as a means to keep the employees away from challenging the unfair acts of the employer. As there is no clause of transfer in the appointment order or conditions of service, the same cannot be enforced unilaterally. This is threatening and it should not be allowed.