Sheesh, a "correction of the OP" but no answer ... great. :)
In any case, TCs can be stored lowered without support especially if the holding tanks are empty. After all, that's the way they are on the RV dealer lots. I'm assuming yours are going to be empty if stored for 6 1/2 months.
There have been a few cases where holding tanks have fallen for a few brands, but like I said, if yours will be empty that won't be a problem. That being said,a number of people use their TCs off truck after arriving at their destinations.
I don't personally support my TC when off truck either with full or empty tanks.
