One of the most important elements of a DR plan is a test schedule. Without a test regiment, the exponential speed of change can put you out of business when a DR event occurs.
Consider a recent situation with a new client. They had 100+ servers on site, backed up to tape. They had a legacy DR plan. Recently they had a flood which didn't affect their network but did motivate them to test restoring from tape. Needless to say, it was a failure. Studies indicate that recovery from tape fails 80% of the time. The solution was to move to a Scarlett Solution and Datto. Datto offers a hybrid cloud solution with triple redundancy, local and cloud. Now they have peace of mind and testing is stress free.