A Very Rare Emission from London

Just came across an example of a very rare London emission. The *T/*F//PLN issue of around mid 310 AD is recorded in RIC referring mostly to examples known from the Boursies hoard. I cannot ever recall seeing one offered for sale or any reported in recent hoards. Looking through CHRB Volume 12 (see June below) at the weekend, I noticed that one was recorded in the Prestwood B hoard and is illustrated. A Constantine with the reverse COMITI AAVVGG. The whole hoard of over 700 coins was acquired by the Buckinghamshire County Museum but there is no mention of it on the Museum website. If anyone knows of any other examples of this mintmark please let me know.