Cointelegraph
Zcash’s November upgrade could freeze funds in legacy Sprout pool

The proposed NU7 change would disable version 4 transactions, leaving ZEC in Zcash’s legacy Sprout shielded pool unspendable.
Cointelegraph

The proposed NU7 change would disable version 4 transactions, leaving ZEC in Zcash’s legacy Sprout shielded pool unspendable.