This soldier wears a General issue button, backed with red felt, in place of a cap badge.
Although this is a good portrait sadly it tells us little. He is either still under training or has just finished. He has not yet joined a regiment.
We should not deduce anything from what we can see. Even the belt and swagger stick may not be his.
The photographer and town may fit in with other information we have, otherwise this image only tells us he was in the army.
Trainee soldier Estimate: 1915
Photograph above embossed Montiville Evans of St Albans Opposite the Town Hall