Ok guys, I think I figured out how to defeat auto start stop being always on for a 21 jaguar. It's a simple 10mm screw you need to remove and pull a cable off that screw on the positive side of the battery. I just did it to mine, after researching some folks who did something similar on an 21 XF and it has worked for one about 10 minute drive with my 21 SVR. I don't want any of you doing this just yet, because I'm going to go another couple days with this cable disconnected and make sure nothing else goes south.
What happens with this cable disconnected from the positive battery terminal is different than pulling that middle cable in the boot under the side cover in the boot on the same side as the fuse box back there on the 2017 to 2020 F-Pace which also defeated start/stop on those years, I have another post out there for that disconnect. For those years, the AutoStart/stop indicator on the dash always had a line through it with that middle connector disconnected. it was that way from starting the car and when the dash was lit, until you turned the car off.
What happens with the 21s isn't so apparent, nothing on the dash changes when starting the car. What happens is when start stop wants to engage the Auto Start Stop indicator comes up on that dash with a line through it, but the engine stays on. That indicator goes away otherwise.
The cable I pulled is the small gauge one that is on the positive battery terminal on the right side of the terminal and gets attached with a 10mm bolt/screw. Simply remove the screw/bolt, pull that cable which has a eyelet on it, tuck it to the side and put the bolt back and tighten it up (I think it may hold the heavier gauge cable that is underneath which is why I put it back on.
In that 10 minute ride, the engine kept running whenever it would normally stop at a light or stop sign, and the start stop indicator with a line through it came up, but the engine never stopped and the indicator then goes off when you lift on the brake.
I seriously doubt this cable does anything else but drive the start stop, but give me a few more days of running this way to be sure.