On the Jaguar forum, I came across a link to (https://powermaxconverters.com/) for a power supply when using SDD. PowerMax is a company in Florida.

I called them. It was after hours EDT when I called from New Zealand, but Errin, the CEO picked up the phone - forwarded to his cell.

He said the PMBC Series ($297 to $509) is recommended for Americans 120V (https://powermaxconverters.com/product/pmbc-12-volt/), but for 120/220V the PM3 12V series is recommended. $150 to $300 (https://powermaxconverters.com/product/pm3-12v-series/). The lower price is because it is just the electronics, not jumper cables.

The 55 AMP 220V is $179, but I opted to go with the 100 Amp $259 ($305 including shipping to New Zealand). While a Freelander 2 needs 20-30 amps to maintain stable voltage, with such a nominal price difference, why not get the more powerful unit?

I will edit this when I receive it to report on how it went.

I only ever used a cheap Chinese battery charger on my Freelander and used to spend hours using SDD trying to figure out problems.
Never had an issue with battery draining. Car is now gone.  Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.