Many years ago it was thought storing the rv trailer for 4-5 months in the winter raising the rv till the tires were off the ground was best.
Times change as does the quality of tire compounds for long term service on the road and just sitting.
If I was going to store the rv for a couple of years I would raise the rv so the tires were off the ground and drop tire pressures to around 10-15 lbs.
For just a few months most tire makers recommend using max sidewall pressures for the duration. And some even recommend the tires be rotated or.....* driven at least every three months to prevent ozone cracking in the tire bulge area, as well as “flat-spotting” from the prolonged strain of sidewall and tread deflection* (*per Goodyear RV tire storage).
I keep all my tires on all my trailers at max psi when rolling or sitting...even my 11000lb 5er.
A book many pages long can be written at all the different ways to lift a rv trailer till the tire are off the ground.
Much to be considered especially the length and weight of the trailer. A short unit may use cribbing under the main frame rails at the front and rear. One jack can lift one side of a short trailer to do this.
Long heavy trailer may need cribbing in the center also so not the bend the frame or place undo stress in the units sidewalls. These size trailers may take two jacks to raise the trailer without bending the frame or cracking the units sidewall.
I would pump those tire to the max till (and keep them at max) you use the trailer next spring.