I suspect that you could (if you tried) still get more nicotine from a vape than you got from your tobacco use, but that does depend on intentionally trying to and the rig you were using.
I have a few friends who have kicked tobacco with vaping, and in all cases they told me that they lost some ground occasionally by tapering to the next lower level of nicotine too soon. So they would drop from 8mg to 4mg a couple of months after dropping from 12mg to 8mg, but get way too antsy and start jonesin' too much, putting them at high risk of bumming a smoke to make up the difference. In some cases they did bum that smoke, and 30 minutes later bought a pack, and found themselves right back at square-1 after ~8 months of tapering.
Vaping a given concentration for at least three months before dropping to the next level seemed to allow tapering without jonesin' too hard to maintain the new level.
Also, in one case it was necessary to vape a 0mg mix for a while to taper off completely with minimal risk of relapse. The funny part of that is while he was vaping his 0mg mix, a different guy I worked with at the time was told by his doc that his blood pressure was at stroke-levels and he had to quit smoking and improve his diet (which was hideous) ASAP. He smoked a few more cigs while telling me about it because it was stressing him out, but then he said "So this is my last one," then he put it out, and to my amazement and admiration he really did quit right then, cold turkey, for good. The day before he'd been a 2-pack a day smoker. I will add that the following week was a very challenging one for all of us at work, lol.
Edited by TVCasualty, 10 September 2019 - 05:24 PM.