Oh sorry @Prollynot I did not want to make out you will be unsuccessful. No one knows your full circumstances. It's definitely worth getting some sort of advice.
Just from my own situation and experience of legal advice and the system I know it's really hard.
Four years after him telling me he was choosing his new woman over his son, I ended up finding an email for him. He hit the roof that I had made contact! This was because everytime I've taken my child abroad I am Subject to questioning. Sometimes their way of questioning has really upset me. This is despite traveling with BC, return tickets etc. It really gets to me how it is ME who provides a life for my child, ME who deals with school, medical, dentist etc. It is ME who deals with everything for my child. Yet because he is named as the other parent I've given him PR. Common sense should be after absence for so long their rights should be removed. You wouldn't be allowed to Foster or adopt without various checks and assessments etc. You wouldnt be allowed to care for any child on the basis you have at some point mothered or fathered a child! His Dad is basically a stranger yet retains his PR. My biggest mistake was forcing him to register his birth with me.
Anyway after 4 years of complete absence and 3 trips to Europe where I'd been questioned about father's permission I plucked up the courage to request exclusive permission to travel abroad and also gave my reasons for wanting to change my child's surname. I kept things really polite and to the point giving very valid reasons. I eventually got a NO.
So I responded and asked for his reasons and he sent me a further 30 odd emails being really abusive and controlling. Which to be honest took me right back to how it felt when he was still in our lives. I literally fell back into the woman i was 4 years ago instantly. His ONLY argument was that he has PR. At this point I was internally raging that he can use the fact he has PR but hasn't for the last 4 years made any attempt to contact or have a relationship with his child. Because he became so controlling I was told to drop contact again. To be honest I had to. I'd spent 4 years working on myself, rebuilding our life for all it to take was some email communication from him to put me right back to the woman I was.
It was at this point I got legal advice. Our circumstances are different to yours it's just my opinion of the system in these situations.
I was advised against any court action as it will bring a man back into our lives who has no interest in his child (he never once asked about him in those emails) and allow him to have control over us again . He has already said no, so on this basis a court wouldn't grant permission for name change anyway regardless of his absence. It's really hard to remove PR and unfortunately if they have it they get a say no matter what. The Solicitor told me to carry on with our lives and never contact him again as he won't bother us unless I bother him and he will never agree to my requests anyway as it is a way to have power and control over me. She advised me to travel as I wish and enjoy our holiday's and just accept that I may be questioned, but without a court order or child protection in place, or him turning up at the airport refusing my child's travel, nothing can actually be done at the airport as they have no powers to stop you from travelling without these official things in place. She also told me my case would never make it to court as he would need to attend and no man like him would ever stand before a Judge and explain why they have made no attempt of a relationship with their child but can cite their PR and deprive a child they have no contact with a holiday. Ive met 2 solicitors in these 7 years and taken with me plenty of evidence of our situation. Lets just say the evidence is CLEAR he is a manipulator, controller, abuser and has no intentions of being a father. It is about controlling me. His PR means he can, but only if I allow it.
It is now nearly 7 years from when he walked out my child's life. I have changed his named by deedpoll and it is accepted everywhere but the passport. When I renewed his passport earlier in the year I tried to argue the case of his dad's absence and his name is accepted EVERYWHERE but they are very strict and said without any orders or permission he will need to travel on his birth name. This is frustrating as my child doesn't know their birth surname but it's not the end of the world as I now know, apart from the questioning I cant be stopped from travelling.
It's horrible when they have PR as they have so much control over you. I remember making a will years ago and being told because of his Dad's PR, if anything was to happen to me before my child is 18, his dad would automatically get 100% PR. I was distraught. Hopefully it's not as clear cut as that and circumstances are taken into account but the thought of him being ripped away from his family and support network is terrifying simply because his Dad is noted on a piece of paper. It's awful!
I didnt mean to explain my full experience (sorry) but an absent Dad retains PR to my child and a court would still uphold his wishes as he holds PR. I know of a family whose father is on the sex offenders list. He still has supervised access to his children (wtf)
It sounds like your ex will knowingly make it difficult for you unfortunately