I searched through my books on Fairmile Bs and found the book "The 13th & 14th Fairmile Flotillas in Burma" which is hard to find but has info on all the flotillas involved. I was very fortunate indeed when this book was given to me by a friend here in OZ as copies are quite hard to find. In the book ML 869 is part of the 39th ML Flotilla along with MLs 868, 871, 873, 4003 and 4004. There is no index so one would have to read through the book to find specific info.
The book Allied Coastal Forces Vol I by John Lambert and Al Ross tells me ML 869 was completed in April 1945 and sold 'circa 1951 in Ceylon'.
HDML 1479 was completed 12 October 1944 and went to the R Neth Navy in 1947. I cannot find any info as to which flotilla 1479 belonged.
Another book is The Banzai Hunters–the fogotten armada of little ships that defeated the Japanese, 1944-45. This book is quite a good read and I'm fairly positive you should find copies via 'bookfinder dot com' a really good book search facility.
This book mentions Operation Dracula, the Allied landings to secure Rangoon which it seems pretty much became a non-event as the Japanese had left.