In order to switch beds on Bed View you must select the nights you want to switch by clicking them, then you right click the selection and click on Switch beds:

After that you can drag the selected nights to the different beds and click to drop them:

If you move the nights to a different date or different room type this window will pop up warning you about the changes and asking if you want to Move without changing the price or Move and adjust the price according to the changes: 

See also:

How to move reservations on Bed View