From what limited understanding I have gained in researching such things, proffer to displace if you think there is a chance that they will not displace everyone with enough hours. If you think that everyone will displace then proffering to displace will only have you lose out on paid move and send you to training sooner. If all FOs with time are moving to the left seat regardless then a proffer will not do anything with regards to what equipment because a displacement will trump those once it comes to that. Someone correct me if I’m wrong. I left an email with a union rep to verify this and they said they would call me but never did.