Tire Pressure

Hey Peeps.
2019 Honda Accord Hybrid Touring here.
Just over 1,000 miles now.
Quick question.
So, recommended tire pressure is 33PSI with Maxx Pressure of 44PSI.
I keep about 35 PSI in my tires regularly and check them once a month.
I plan on doing a road trip with 4 people and trunk full of luggage, camping chairs and loaded cooler.
A heavy load.
What tire pressure should I put in the tires for a mainly highway trip?
Thanks in advance for all your opinions.
Bri.