Banderas is the latest addition to the EX3 cast. Being from Spain the spanish media reacted rapidly to the news and is suggesting that Banderas has been called to replace Willis! A couple of Bulgarian outlets have also reported that Banderas will not start filming before the 2nd half of September.
It is clear that Banderas will not play Church but instead of deleting Willis' scenes, it's a possibility that Stallone have Banderas take over the scenes with some minor rewriting. If Banderas is replacing Willis, then he will have a minor role as Willis was supposed to (Willis was going to film for 4 days only). Banderas as a secret service agent in EX3?