can anyone figure out my new leaf issue

This is not magnesium 4sure. It has totally different patern. They were fed heavily, then recovered well, now you changed formula and ask us why ? To me it looks like signs of hunger more than anything else, i would triple check isn't nutes old and of course my favourite PH. Fox farm trio is very strong, i used that line years ago, could be that too, despite me thinking, that you learned overfeeding lesson already.

It's Bit early for bloom, wait untill there some sort of flower growing .. keep that veg feed going, there quiet pale saying give me nitrogen.. up to you but that's my advice pal.gl

Unfortunately, many different things can cause chlorosis, and this is only starting. How it progresses will help figure it out. If this is soilless/hydro, it's even easier if familiar with the formula you use... it shoudl stand out if something is too low or two high. i don't recall tiger bloom being overly concentrated, so it's probably something that pre-dates that. This stuff doesn't typically happen overnight except in extreme cases. When there is a Mg deficiency, there's even a 4-6 week delay from onset to visible symptoms in leaves -- the only nutrient with that long of a lag effect to my knowledge. too much p or k could cause some chlorosis, but it would be in the new growth at top. you'd also see some skinny blades forming. if it's only at the top, it could even be light-caused with similar symptoms as just described. when it comes to diagnosing, leaf symptoms are usually not enough on their own. Leaf symptoms are indiscrete.

Nothing really to worry about toooo much but if you want to spit hairs and be critical it looks like slight Magnesium issues starting. My guess is the bloom is knocking the balance of nutrients off. I've noticed his with my plants late veg around the time I apply flower fertilizer. Sometimes I start seeing slight magnesium issues If i overdid it. Calcium, potassium and magnesium antagonize each other for uptake so need to be in a balanced ratio. The next time you water give them some Epsom salt, and you could even do a foliar spray now of it right now and the plants should respond almost immediately. Some micro and macros found and rock dust may give you some good results too. Basalt has lots of magnesium but takes some time to break down.