I don’t talk much, so I can’t be completely sure, and you never know with your own voice anyway, but I think most of my native Northern Irish accent has come back.
I never had a strong accent really, but I don’t know if this was because my working-class parents accidentally sent me to a middle-class primary school (rectified, fortunately, with transfer to secondary school), or whether it’s just the fact that I was born with a good ear for the sounds of language.
It does surprise me somewhat that people who read newspapers (of which even the lowest-quality use moderately correct English) or who obviously understand the likes of Trevor MacDonald or Ian Hislop or the Queen, still speak with the unique sounds and grammar of their own dialect. One common pattern in Ulster English is to swap “seen” for “saw”. “I seen” is common, and even “I have saw” occurs often enough.
I don’t say things like that, well, because it’s wrong. If you’re using the English language to communicate, then sticking to the standard forms is more likely to be successful. On average, at least.
I think I must have absorbed enough non-local English for my accent to be fairly muted even by the time I left school, because I remember in my first year at University in Edinburgh being introduced to a girl at a party. We chatted amiably for quite a while, and then my Scottish friend who’d introduced us came back and said “Ah, I thought you two would get along, since you’re both from Northern Ireland.” And we both went “Oh, are you from Northern Ireland?”
When I started work, I worked with a lot of people of different nationalities, particularly from America and India: both countries with an English that diverges from British English. I even became pretty bilingual in British and American, and sometimes found myself acting as unofficial interpreter in meetings. I wouldn’t say that I was ever fluent myself in Indian English, but I certainly did develop the ability to “tune in” to the different accent and rhythm.
On more than one occasion, an English visitor to our office in Belfast would ask me “How long have you been over here?”, assuming that I was English myself. But I don’t think it was that I had an accent similar to that from any part of England. I think my accent was probably “neutral”, with few Belfast features.
Although I have, from time to time, caught myself unconsciously imitating the person I’m speaking to. My sister-in-law is from South Wales and has the famous sing-song, look-you boyo, there’s lovely voice. I hope she’s never thought I was taking the mickey. Probably not. She’s probably just thought, “Well, now he’s talking proper. Isn’t it.”
Having an ear for accents, I can often pick up the original location. Of course, most locals can recognize differences within their own region — an Edinburger knows an Aberdonian, or a Belfastman a Derry Wan, hai — but I’m quite proud of my ability to distinguish, say, a Canadian from American, or New Zealander from Aussie. I’m not so good at imitating them though. I’ll just stick with what I’ve got. Whatever it is.