I wonder if letting the pressure treated dry a bit first might help. I know that how they do it now, vs how it USED to be done is entirely different.
I picked up boards, and carpet last Sept and was going to do mine while we were on vacation at Hartwell. Then the truck was so darned full I didn't have room for them.
I routed the edges of the boards, drilled and countersunk the bolt holes, and they've been sitting in the shop in the basement ever since. I know new PT lumber weeps for a while for sure.
Makes me think about whether or not to use a Brazilian hardwood. I built new decks in 2016 out of Ipe (eee-pay) wood. (Or Ironwood to us old guys.) This stuff isn't cheap, but it doesn't burn, doesn't rot, is insect resistant, is INCREDIBLLY DENSE @ 60lb per cubic foot, and will literally last 75~100 years. It's actually MUCH cheaper than the top of the line Trex or similar composite product. But it's really REALLY hard. (At the time, top of the line Trex was $60 a plank.
The decking boards, 144" x 3/4" x 5 3/8" were $44 (with grooved edged for hidden fasteners).
I haven't priced it compared to Ultimate boards, but I can ASSURE you it's less. Not normal to see it in 2x4 but it's out there. Probably in the $5 a foot range for Ipe.
Of course Ipe is the most expensive of the Brazilian hardwoods. There are many different ones, like Cumaru, Tigerwood, Purple Heart, Jatoba, Garapa..... and they are all better than pine or cedar for that matter. Massaranduba is a redwood, and likely would work great.
Think I might call my guy and check on that for my 'summer' project.