Details about how Growatt works

I have 12 250W solar panels, a 6.5kWh Growatt battery, and a Growatt hybrid inverter. I have a question about how the inverter behaves. If the battery is not fully charged, and the solar panels are generating something (say 1kW), but not the full 3kW required to charge the batteries as fast as possible, what happens:

  1. Does the inverter take the 1kW from the solar array and 2kW from the mains import, so charging the battery at the full 3kW rate?
  2. Or does it take the 1kW from the solar and nothing from the mains, so charging the battery a lot more slowly than possible?
  3. Or does it take 3kW from the mains, and nothing from the solar? In which case, where does the 1kW from the solar go?

Thank you - Rowan