It can vary for everyone but it took my LG about 4 days to crack the basics and any accidents we had were more misses of not getting to the toilet quick enough. Within 2 weeks it was as if day nappies never existed. It does take some kids a bit of time to adjust getting used to under pants but even then it only takes a day or two for them to adjust. We did have a minor regression about 4 months in where she would say "I need a wee" but then go right there but that only lasted maybe a week. 8 months later and we only rely on night nappies and can get away with only carrying one pair of spare clothing (though I carry more just in case)
) and even then not had to use them! You have to be committed and really responsive when they say they need to go, which Shan probably hasn't been. Pretty sure she started potty training well before my LG started too. I know it's not a competition but it shouldn't take that long to still not be mostly accident free.
The oh crap book is what we used for daytime training and really recommend it. My biggest tip is when they do have an accident, don't make it a big deal and try not make any loud noises as that can make them think they're doing something wrong and can lead to them holding it or going to hide and do it.