As of 19 July the following were updated.
UK, Household Cavalry Records of Service, 1799-1920
Now 17,653 records
UK, Officer Service Records, 1764-1932
Now 132,421 records
UK, Royal Air Force Muster Roll, 1918
Now 194,814 records
UK, Military Deserters, 1812-1927
Now 302,802 records.
Also, new on Ancestry as of 20 July, Aberdeen, Scotland, Roll of Honour, 1914-1918, 1939-1945 for 8,186 individuals, name, residence street address, death date, military rank, military regiment, and more depending on time period. It includes over 300 men who served with Canadian forces. Check with www.cwgc.org for possible additional information as well as in LAC service files for the Canadians.