I have asked my Dutch dealer this morning. There is in fact a major update available with the 100 kw charge update in it (it was expected in January 2019), but it also has to be installed by the dealer because the whole system (i believe 6 or 7 modules) has to be overwritten and it will take at least 4-6 hours. They tried to install it on their democar but it did not proceed after starting it, so JLR first has to make some adjustments for the update in order to be installed properly.
Furthermore, the update will bring a broader OTA option but some major updates (eg. for motormanagement) will still have to be installed by the dealer as long as there is any risc of a car not getting through the update and then has to be put on transport to dealer. As soon as JLR has refined the update process (with an automatic reset to the old systemversion in case of any problem whilst installing the update) the updates can be distributed through air.