We have several girls that do back uprises (no shaposh though... just as an extra B for high school or L8). We have a L5 training L6 that has had an uprise for over a year. I think there are at least 10 - 12 girls in our gym that do them
At my gym we teach uprises to the girls too. In some cases as a save incase a high bar skill goes wrong - for example some of our girls who have only recently got their high bar upstart/kip have been taught to uprise so that if they miss the upstart they can uprise and still get credit for a move so they don't get a short routine.