Daniel lists CM3/960 - 976 as relating to Gen Hospitals Nos 1 - 17. I have however come up against several anomalies with this.
I am attaching scans of a postcard and cover from AK's material, both posted in September 1915. The card bears CM3/963 and is franked APO S13, which Proud places at Le Treport at that time. The picture on the reverse is of No Gen Hospital No 3 at Le Treport. However, Daniel lists CM3/963 against No 4 GH.
The cover bears CM3/964 and is franked APO S6, which Proud places at Versailles. Daniel lists this as No 5 GH, which according to the listing on the website The Long Long Trail was at Rouen at the time. The listing gives No 4 GH as being located at Versailles
I have also seen a cover on War Covers with CM3/965 and franked APO S15, located by Proud at Bruyere Camp Rouen. There is a letter inside which is addressed from No 5 GH, although Daniel lists this CM No as from No 6, also at Rouen.
With these apparent anomalies, I wonder if the listing in Daniel has slipped a line, i.e. it should run from 961 - 917. If anyone has any records which would support or disprove this supposition, I should be pleased to hear
Here is the cover