The redeem time is the block time.
The redeem time is the timestamp of the transaction. It's the time the tx was broadcasted to the network.
The block time is the "confirmation" time. It's something else.
There would be no way for us to reference tx broadcast times for historical redeemed coins without trusting the records of a block explorer such as blockchain.info as transactions don't carry this info. Also, the tx time you see on block explorers is actually the time their respective nodes received the tx.
This is why I decided to go with block confirmed time as the redeemed time; it's completely fixed into the blockchain and immutable.
Technically speaking, the 'true' redeem time is when a coin is physically peeled :p