Terry plans the move after his teenage son TJ doesn't react well to the arrival of his baby, while Terry's own relationship with Bianca Butcher is also far from rosy.
Here, Terry Alderton - who plays Terry - chats about the drama in store for his character in the build-up to his exit.
How does Terry feel once he becomes a grandfather?
"Terry gets on with the fact about being a granddad as he always does, because problem solutions and looking on the bright side is what he's all about. He has got to see the best out of what is obviously a bit of a nightmare situation, which is his son of that age having a child and children having children.
"I think behind the scenes it would be quite stressful. He also doesn't like it that Phil Mitchell is muscling in on things - that doesn't go down well!"
When TJ admits that he is freaked out and doesn't want to be a father, how does Terry react?
"Terry just thinks that TJ is being silly. He's like, 'Don't be daft, let's speak about this'. After a while, TJ tells him he doesn't want this. Terry is astonished as he has been so wrapped up in himself. His whole adventure of making things right is no good if he isn't listening to his son!"
Why does Terry initially decide to move to Milton Keynes?
"Because his sister Val has said there is some redundancy money coming and he is always toying about setting up his own company and being his own man. Terry has decided maybe that is the place, because his sister lives up there. He has investigated setting up a cab company that will bring something else to the area and a fresh start with his kids."
How would you describe Terry's relationship with Bianca at this point? They have been secretly seeing each other, but it seems like that isn't really what Terry wants…
"Yeah, I think that Bianca is finding herself, really. Terry has gone along with the whole situation because he thinks he's on to something more, and then he realises he isn't. That's when Terry prepares to go and Bianca thinks, 'Hold on a second…'"
Bianca seems upset that Terry is leaving and blurts out the news to Alfie. How does Terry react?
"Terry is thinking that Bianca is being spiteful at that point, as she announces it all to him and the world and Terry hasn't even told Alfie yet! He thinks that she's just being malicious, and I don't think at that point Terry realises that actually there is an underlying thing going on there…"
But when he does realise, he kisses Bianca and tells her that he loves her…
"Yeah, he suddenly realises that he hasn't been listening to TJ and he realises what he wants. Now he is saying to Bianca, 'I might as well be honest with you, and if you can't be with me then forget it'."
Is Terry genuinely willing to go without Bianca?
"Yes, he'll go. He needs to move on."
What would it mean to Terry if Bianca did decide to go with him?
"Well I think that he would be elated. He would get the girl, wouldn't he? She would get a man and that would be a lovely happy ending, that would. Terry also sees himself as a bit of a saviour as well. He can see Bianca's life is a mess and that he can make her life a little bit better."
Has TJ's negative reaction to the baby strengthened Terry's decision to move?
"I think that it's made him realise that he's been selfish and hasn't thought about his son's real wishes. It's a concern that he hasn't realised that."
What have you enjoyed the most about your time on EastEnders?
"I have just loved every minute of it. I like the stability of the job. I was doing stand-up, and I got to a point where I didn't want to do that anymore and this came along. At first I didn't want to do EastEnders, but then when I did I actually thought to myself, 'I really like this'.
"I've been very blessed having 25 years travelling the world doing stand-up and having the family of the age it is, I just think it is a great joy just going in and doing that. It's like making little movies every day - I loved it."
What's the funniest day filming you've had?
"Without a doubt, in The Vic when we were filming a scene where Bianca was talking about Carol's tests. There were a lot of us in there - me, Patsy, Jessie, Danny Dyer, Rachel and a couple of others and I just started laughing. Jessie and Patsy always start but they manage to hold it together.
"Danny had his back to us and I kept hearing Danny go, 'C'mon we can pick this up, we can do this'. He wasn't facing us so I just thought he was being encouraging, but it wasn't until he came over and put the drinks down and did a massive pause and looked up and he was absolutely crying with laughter! It just went on and on and on. It was just brilliant, it was just so funny. When you watched it, you'd never know."
Who will you miss working with the most?
"Shane [Richie], he's my mate. I'll miss everyone but Shane really is who I'll miss working with the most. I work brilliantly with Shane, he's just very easy and he's very natural. We do everything straight on, straight off - a couple takes and we would be done."
What kind of reaction have you had from EastEnders fans?
"I've had people shaking before saying, 'Oh I love EastEnders so much'. It's different though as I get recognised for my different roles. I get the double Terry - Terry the comedian and Terry the EastEnders guy. I never know which Terry they are coming for!"
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EastEnders airs Mondays, Tuesdays, Thursdays and Fridays on BBC One.
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