Found on Twitter from Dr Helen Fry | WWII Historian @DrHelenFry
They were called "Hush WAACS" and were posted to the front line in France. Their top secret, primary work was to decode messages. They were the early codebreakers and Mabel Peel was one of them.
Mabel Dymond Peel (1879 – 1938) was born in Barton upon Irwell, Lancashire, UK, in 1879 – the birth being registered in September of that year.
The Hush WAACs were a group of seventeen British women who worked on the front line as codebreakers in France during World War One. After the war, two went on to work on diplomatic codebreaking for MI1b. Although women were already working as codebreakers in Room 40 and MI1b, the Hush WAACs were the only women to serve as codebreakers at the front line during WW1.
In 1917, the British Army in France was short of manpower, and members of the Women's Army Auxiliary Corps were asked to volunteer for front line service in supporting roles. Six women were identified as capable of supporting the I(e)C front line codebreaking work at Saint-Omer in northern France and arrived there on 28th September 1917. They had not been told what their duties would be.
They were joined by another three women who found conditions too difficult and returned to England. Between 1917 and the end of the war in November 1918, a total of seventeen women were sent to work in the I(e)C codebreaking team. There were typically around 12 women in the team at any time. They were aged between 22 and 55 years old, and had all volunteered for front line duty. All were middle or upper class, and spoke German.
Sources: https://www.gchq.gov.uk/information/hush-waacs
Wikipedia, Find my Past, FreeBMD https://welwyngarden-heritage.org/news/miss-mabel-dymond-peel
Dr Fry has written a book entitled “Women in Intelligence” :
The book is a history of women in British military intelligence from 1914 to 1945 – available to purchase from https://www.helen-fry.com/women-in-intelligence
