Workers at the Port Kembla Coal Terminal are unlikely to "cut their losses" and accept a pay deal from the company.
In March last year, the Fair Work Commission struck down the agreement covering the workers.
The commission ruled the expiry date would take effect 12 months later, to give both parties enough time to reach a new agreement.
That deadline of March 29 is fast approaching and if no agreement is reached by then, the workers will be covered by the standard award.
That award has fewer conditions than the one now being offered by PKCT.
CFMEU southern district vice president Bob Timbs felt it was unlikely the workers would accept that deal to avoid being in a worse position come March 29.
"That would be a decision our members would make," Mr Timbs said.
"It wouldn't be a decision I’d take back to them, saying 'hey, cut your losses, we've done all this for nothing. Let's pack up and go home'."
The workers are now locked out for the third successive time and cannot return to work until Monday.
Combined with strike action, it means workers have not been inside the terminal since January 18.
The key sticking point is a job security clause that workers contend will allow the company to sack them and replace them with contract labour.
The company has said that is not the intention.
Mr Timbs said, if the March 29 deadline came without a new agreement, the fight for a better deal would not be over.
"I think that's the company’s strategy, to put us back on the award and say 'now you've got to battle back from the award'," Mr Timbs said.
"The company's thrown everything at us that they could possibly throw at us. They’ve basically offered us pretty much the award at one stage.
"For us, although the agreement will be terminated we’ll still be trying to negotiate for an enterprise agreement that delivers job security for our members."
PKCT was contacted for comment.