@SativaKid
Well, I’m not sure if I know what the right answer is with certainty yet, this summer has been an experiment so far. If you just want my answer to your question, it’s at the bottom of the post. The rest of this explains how I landed on that answer.
What’s generally recommended is a small amount of airflow over the buds, hold 60F at 60% RH and it should take 10-14 days for the bud to be dry enough to jar (somewhere around 10% moisture content in the actual plant material).
Because my box is in the shed, it’s subject to whatever the weather is. In my case, it’s been hot. WAY hotter than 60F. In any case, you don’t want to exceed 70-80F because some of the volatile monoterpenes just evaporate off immediately. So I designed a thing that basically averages out the day and night temperatures using a big water cooler full of water that pumps through to stabilize the temperature. Now that it’s cooler at night and daytime that’s working pretty well, and holding around 64F. Earlier in the summer I had to add ice to the water, and eventually a cooler setup to keep the water/air temperature below 70. But the temperature varied throughout the day, often running 60F exactly though the night, and sometimes as high as 80F during the days (it’d be 100+ outside the shed). Hindsight, I would have just built this thing in a fridge. But hindsight is hindsight because it’s too late to change now 
maybe next summer.
Anyway, at 60% RH, a temperature of 70F will cause the drying process to take much less time. I hypothesized that keeping the Vapor Pressure Defecit (VPD) constant, and adjusting the humidity to match, should equalize the drying rate so it takes a similar TIME regardless. So, my exhaust humidity level (again, this is experimental) changes based on the temperature to produce the same VPD. I don’t really care about the RH level, I’m trying to maintain VPD. That’s not typical, but I think scientifically it makes much more sense.
Here’s the same chart posted a few months ago when I concocted this scheme:
A higher number indicates water evaporates FASTER. Low numbers mean evaporation will occur slower. This is based on partial pressures, and the difference between the material and the air itself.
So, if you just look at that chart you can get an idea of the trend - between 50F and 80F the VPD stays around 0.7 if you match the RH to the temperature. The highlighted green box are the purportedly best zones to dry according to the internet and various books. So, I picked the VPD at 60%/60F which is the most popular recommendation, and said, regulate to a VPD of 0.71.
Of course, since I wrote my own code, I made it more complicated. There is another humidity sensor that measures the RH/T of the air by the intake filter, and I calculate how much water there is in the air. If that’s more than is inside the box (if the outside air has more water in it than the air I’m trying to dehumidify - exhausting would only make my problem worse), then I activate a small dehumidifier. If the air outside is drier than the air I’m trying to dry, then I simply pulse the exhaust fan on for a few seconds. Normally the dehumidifier has only run when it’s raining outside.
I have noticed the best results with a small air turnover in the cabinet. The circulation fans run all the time, regulating the temperature and ensuring my sensor in the box is measuring the air flowing over the buds. This runs really slow, but noticeably so. I’d say the air in the drying stack travels the height of the stack in a few seconds. I have a MERV-13 filter in this airstream before flowing over the buds, which should remove any mold spores and dust from outside, there’s also a dust filter on the air intake. The exhaust goes through a carbon filter to keep my shed from stinking.
In simplest possible words, my RH is approximately equal to my temperature. If you have a humidistat and want to follow my relatively unproven path, set the humidistat to be equal to the average temperature. In 2 weeks or so, your bud will be dry and I’m very encouraged by the results.