As more and more Galaxy S5's are being updated to Android 6 Marshmallow and as Android 7 is soon to come out is there any chance of the S5 getting an update anytime soon as mine is still on 5.0 which given the various android security updates etc. over the last year could be a cause for concern?
But, as JOhn said, VM are ALWAYS the last operator to update, and probably this will happen just before 'nougat' appears. VM are not just slow, they are basically snail paced regarding anything that might just make life easier for customers!!