However, on 10 August the TF was invited to volunteer for overseas service, and the majority of men and units did so.
Those who did not volunteer or were unfit for overseas service were separated on 15 August to form the basis for reserve units to train the mass of volunteer recruits coming forward.
At the same time the remaining home service and unfit personnel were separated and grouped into coast defence brigades, shortly afterwards termed provisional brigades.
The provisional infantry battalions were numbered up to 108 (with some gaps in the sequence).
The provisional brigades thus became anomalous, and on 1 January 1917 the remaining infantry units became numbered battalions of appropriate regiments.