I wean off direct latch my girl when she was 15 months when she starts to bite... Introduce her fresh milk when she was 12 months for her afternoon milk in straw cup. Gradually wean her off when she was 15 months. Drinking frozen bm and fresh milk in straw cup instead. After that fully on fresh milk in straw cup.
Working mum here so no choice has to stop direct latch very early. For the older kids - have a pact with papa that he needs to extra sayang them while you are busy with new baby