Changing subimage but keeping sprite

[prime notch]

i have a skin system, with a 360 rotational sprite for when you move by rolling around. i want the skin to only be determined when spawning in, instead of calling the sprite every frame you are moving to increment the subimage. essentially, just setting the circled value to "keep current sprite"

btw setting it to "No sprite" shows an error for trying to change to a non-existent sprite, but technically does keep the sprite