Please tell me this isn't Bud Rot!?!

"but the best way to catch it early is the leaves start dying off! " -- this is referencing the sugar leaves.. possibly fan leaves if they are pop out from the buds too. your sugar leaves wil all die off in the infected area. why fuzz at first, then grey, mushy nonsense late. just get a cheap 100 pack of stripps that resolve within .5ph with 4-colors to split it up pH range for easier resolution. it'll end up being a similar cost over time for calllibration and replacing the sensor periodically... plus having to buy and store 2-3 callibration solutions etc etc... 1281 ppm, if accurate, is an incredibly high dose of nutes. (*just an afterthought.. is this measured with tap water or calculated from labels? if with tap it's not as bad as i make it out below, but probably still too high unless your tap water is 500ppm range.. even more reason to calculate from the labels to guage balance of mix - shouldn't need more than a 1.5ec mix of nutes and hopefully not too hard of tap water).. if it is missing calcium, i'd be surprised and you should change brands if it is the case, lol.. again, i doubt it but possible. (google "ferilizer ppm calculator manic botanix" and see how much Ca you provide before assuming it is a Ca issue. can eliminate a lot of what-ifs and maybes with a modicum of effort.. plants will thank you) This is a bit more complicated with soil as some was likely in it to start... your tap water will cause variation in Ca/Mg needs compared to others too. nonetheless, if you take note of these things you can learn a safe zone and find a good balance faster than only reacting to the plant's physical appearance, which can easily be decieving when working with limited info. Anyway, at nearly 2.6ec you are at an upper range of short-term limits of the plant and well beyond its long-term metabolic rate of use. A plant can technically survive at 3ec but you don't want to feed it that much on purpose. I'd wager this is a toxicity causing lockout, so you'll see any number of symptoms that aren't actually the cause of the problem.... or in the case of 2.6ec, potentially more than one necessary molecule is too high concentration. on top of that you are in soil, which came with nutes built-in. The diary says you've also been fertilizing since week 1 -- at what i assume are instructed levels on the label? It's almost certainly overcooked. balance is key to fertilizing. It's more of a trial and error path with soil than soilless or hydro. if you change soils, you may have to re-learn that balance, but it is always easier the "2nd/next" time. if you use soil, let the plant eat it up and slowly ramp up fertilization over time as the soil requires more replenishment of nutes. Remember it is always easier to ramp up in reaction to a minor leaf issue than it is to fix any toxicity. unless working with a living soil, you end up providing near 100% of what is required by the end. if you want a ballpark of what that looks like, my (for soilless*) ppm table is in nearly any diary or week. i have hard water, so my ca/mg may be more than a few percent off from what you need. the npk values should translate to any 6ish pH range. higher pH may want less N among any other minor adjustments needed.