Research! [I have too much time on my hands, it seems.
]
Here's a gymnast doing a free jump to cross split mount on the balance beam.
And the description on page 107 is for balance beam mount 1.305D:"free jump to cross split sit - take-off from both legs - diagonal approach to the beam.
But Ms. Dick apparently added a new element in 2015, which the protocols for judging the World Championship in Glasgow acknowledged by
amending the description of the move. So the description for balance beam mount 1.305D now reads: free jump to cross split sit,
also free jump with legs change to cross split sit - take off from both legs - diagonal approach to beam. [italics in the original]
So, it's the legs change that she added to the move. It does look very like the original version, but I'm guessing it makes the thing much harder to do. Kind of like those ice-skating moves where the skating commentators are all agog at an edge change that doesn't look like a big deal to a non-skater.