Agreed they are not on the GP List YET....
And Being it is not on the GP List Brent is correct, these notes ARE NOT YET CONFIRMED.
All the Fully Detailed Brick info regarding these Inserts will be in Gary's hands on the weekend, then it will be forwarded to Gilles to be added to his findings. I got the Inserts almost a Month Ago now. They were usually found in bunches of 12 at the usual spots between the 250 and 251 Notes , 750 and 751 notes.
The bricks they were found in were HOY Serials 5.39 - 5.40
If you wish I can provide all the Front and Back plate numbers for every one of the Inserts that also match the HOY notes on either side.
The exact range is unknown as more finds are required to figure this out. (All found between 2 Bricks), All serials ending from 40 - 51.
To see an Example Search eBay for HOW and you will see the only Set I have for sale. 8-)