Verizon has to be the slowest for releasing system updates.
I cannot find any info on when marshmallow will come out
for Verizon phones.
Unfortunately no timelines have been published for the software updates coming to the Turbo and Turbo 2 phones. Rumors have it that the Turbo 2 software is nearing completion, as a few weeks ago a test update was pushed to employee versions of the phone. As for the original Turbo, I haven't heard anything new yet, other than it will be getting the update.