Hi, new M3P owner here in New England. I just read through this whole thread, which went in many different directions, but seems to have gotten back on-subject. I was surprised to learn that the jack points are aluminum and are part of the battery.
That raises the question as to how, during the battery replacement, do they hold up the rest of the car?
I was impressed with the many different techniques discussed for jacking up the car. I have made adapters out of hockey pucks and rubber bumpers, which can be seen in the picture below. At left is my old 3.5 ton non-low-profile jack, which goes down to 5" high. If you first plug the adaptor into the lift point, it just clears the highest point of the jack cup as you slide it underneath.
A recurring concern, with just one jack point per corner, is safety while using floor jacks. While solutions exist, I am trying to work out a low-cost alternative using 2 standard or low profile hydraulic floor jacks on one side of the car at a time, e.g. for rotating front<-->rear. It will also work with one jack on one corner at a time. I agree with those who have concluded that there should be no problem with tweaking the battery, which is repeatedly tolerated during normal driving.
The key idea is to leave the jacks in place and achieve safety by inserting something within the floor jack so it cannot collapse, even if hydraulic pressure is released for whatever reason. Most jack stands are too big for most jacks, but I found some 2-ton steel ones at Walmart for only $10 each that measure 5-5/8"x 6-1/4" at the base and extend from 10" to 15" in steps of ~3/4" (see photo). These stands fit within the side rails of the old 3.5 ton jack and, in one orientation, in a new 2.5 ton Aluminum low-profile jack. To use them, jack up the car perhaps a bit higher than desired, then insert the small jack stand within the jack, then extending it as necessary to provide a back-up. Alternatively, a block of strong wood could be cut to fit the space under the jack.
I haven't actually used them yet and a few details, like how the top of the jack stands mate with the undersides of the jack without bending anything, need to be worked out. I just wanted to see if anyone is interested or has done this and how it worked out. I will post again after beta test.
There is plenty of time now with COVID-19 lock down.