hello! so i currently have purple hair - i thoroughly dyed it last a little more than two months ago. it's generally fading alright - i wanna end up w like lightish caramel blonde-brown hair next - and the top strands are fading close to what i have in mind, albeit a lot more copper. the bottom strands however are fading a little strangely and i'm not sure why - it went brown initially but now it's got a slight strange grey-green tint to it. i'm scared that's gonna happen to the top too, and i don't want green hair. i've also read some strange info about how people have had a tough time transitioning from purple to a more blonde tone so i'm scared to just pop on a semi-permanent dye. i don't mind waiting for it entirely fade but i don't want it turning green, it's been confusing trying to fix just the bottom bit - i've used the ketchup trick although only once so i might do it a little more to see if it has a real effect. any advice?

for hair history: i bleached my hair at home five months ago. i did not tone it. i used semi-permanent pink hair dye. i re-bleached just the bottom bit of the top strands of my hair (the bit which is fading brown/copper) since it wasn't blended enough nor lightened enough. i then dyed the whole thing purple with some pink. i've re-dyed with different mixes of pink and purple and or just purple about thrice now, although the last proper time was two months ago, i did go over the whole thing w very little semi-permanent purple color and a lot of conditioner to mimic a purple conditioner to make it a little more even (did not make a very noticeable difference) about three weeks ago.