No exact day, but August 2015 I was smoking almost 50 a day, after starting smoking again 12 years ago, going through a stressful time and I made the mistake of bumming a smoke as a way to chill out... Bad idea! (I'd experimented as a school kid as most of us do, but was convinced of the error of my ways after about a year of sly fags). Anyhow, having tried so many times with patches, sprays, cold turkey and always going back, I tried a cheap ecig, and although I didn't stop, I managed to cut back on the cigs, until it broke, then more stress through redundancy led me back to full time smoking, I gave up trying, typical addict behaviour.
My son came over one day with a Kanger Evod, which I tried and found quite good, and didn't give it another thought. It wasn't until 3 hours later I realised I hadn't lit up since he left, which was a long time for me. I bought an Evod 2 the next day, and I was down to 2 a day inside a week.A month later I bought a Subox mini and haven't really looked back, the real turning point was finding a good all day vape (Ruthless Slurricane), but I save that one for a treat a couple of days a week.
Since then I've had a few periods of falling off the wagon, maybe 5-10 a day, but they're few and far between now, and I'm down to 3mg, partly due to the sub ohm being too much to take on any more than 6mg.
While I dont see myself as a truly quit, ex smoker yet, (I wont feel like that until I'm down to 0 nic), I'm amazed that I've got to where I am, I never thought I'd manage to kick the cigs, but thanks to the knowledge of my local vape shop staff, and the support of my wife who keeps me in check when I feel like lighting up, I'm happier and healthier than I've felt in years, and the satisfaction I get from tinkering, building coils and now DIY liquids is great.
I'd urge anyone like me who has tried and failed to try this, you won't regret it!!