segregated witness – How can a replace occur with a tx with lower fee and feerate? – Beragampengetahuan

I have seen a tx A get replaced by a tx B, where B had a lower fee and feerate than A and it was broadcasted later. How is it possible?

These are the txs details:

• Tx A: segwit, ̶t̶a̶p̶r̶o̶o̶t̶, ̶R̶B̶F̶
• Tx B: segwit, ̶t̶a̶p̶r̶o̶o̶t̶, ̶R̶B̶F̶, Full RBF

Can anyone help me understand it, please?