Possibly, except that the men who are or appear to standing on the destroyer or the gangway(s) are all facing towards to the quay, as though getting off rather than on. Many do not seem to have rifles at all and that being so, one would expect such "spare" rifles to have been handed out to them for embarkation?
Possibly the collection of rifles from men who had done exactly that: picked up loose weapons or weapons not actually issued to them and brought them back? Those who have rifles don't appear to be turning them in; perhaps their issue weapons?
The apparent absence of officers or NCOs is interesting.
it certainly does look to match Dover - great 'find'.
Mine are not the best, but they are not too bad. I can think of lots of Enfields I'd rather have but instead of constantly striving for more, sometimes it's good to be satisfied with what one has...