Changing baby boys name day before we are having him...

So my husband comes to me last night as we are getting the bags ready for the hospital and suggested we change the name of our baby boy. We had the dna test done so we have known since 12 weeks that we were having a boy so we have had his name picked out for a while. We had agreed on Gunner Jay now I compromised on both names. Neither was my favorite but Jay is after his grandfather. Well long story short our first son is named after someone on his father's side and this one was going to have a name from his mother's side. Well his dad guilted him last time he was with him saying he guessed that he would never see the day a grandchild was named after him. Now my husband wants to name our baby Gunner Rocklan Jay.. or Gunner Clive. I'm struggling because I already have gotten used to calling him Gunner Jay. What are some thoughts on this? How would you handle it?