When charging at work on 20 amp L2 the app always says time to charge complete but displays elapsed time of charging. Around 5% to 8% remaining to charge it will count down giving the correct time to full.
Sounds reasonable. The balancing charge is done with 1/2 phase(120vac) and can be very slow sometimes. I don't have battery instrumentation for the Jag , but my Ford Focus Electric had it. A full charge was 16kw(from a 23kw battery). On 1 charge it balanced up to 16.8kw.