Ukrainian pilots are currently flying with Maltese license validations while awaiting the completion of the necessary exams to obtain their EASA licenses. At present, they are the backbone of the company, willingly taking on tasks that others would never agree to.
Until they acquire their EASA licenses...
As for the contract situation, my opinion is that the company will gradually replace the non-compliant individuals (those who have not signed the new contract), one by one, as new pilots complete their line checks and sign the new, less favorable contract themselves.