The final TON was mined at around TKTK, signaling toncoin’s transition from a largely proof-of-work (PoW) model to proof-of-stake (PoS).
Source
Final Toncoin Mined Ahead of Transition to Proof-of-Stake

The final TON was mined at around TKTK, signaling toncoin’s transition from a largely proof-of-work (PoW) model to proof-of-stake (PoS).
Source