Time zones in Belgium 1915

[O1dgobbo]

Hi

I have been researching the activities of 8th Bn DLI in mid-April 1915 (2nd Battle of Ypres). Most of the accounts I have seen and the British War diaries seem to be using Greenwich Mean Time. Am I correct in thinking this and if so what was the time used by our Belgian and French allies. (If they were using a continental time it perhaps explains why it was so difficult to coordinate counter attacks.)

All the best

Gobbo