@k00b and @039802da15 My thanks to you both (a bit of a 'head slap' moment for me!). The cli echo commend is in fact directly from the Bitcoinmagazine feature, so I'm now thinking that it's an incorrect method. Time will tell, because if the checksum is not correct, a Wallet such as Sparrow will not accept the 24 Word Seed. I know that the Electrum Wallet does not do that check (I've tried it), so any random collection of 24 BIP0039 Seed Words will work. Thanks again; back to it :)