It is difficult to give you any advice regarding the operative follow-up without knowing the importance of the lesions or the style of surgery that will be performed.
I can answer you that at the Clinic of the Union, our surgeons all operate under arthroscopy which makes it possible to dress normally (by respecting some instructions concerning the not working of sutured tendons).
It is possible to remove the splint but respecting a gap between the arm and the body if your splint is called abduction. In general, it is necessary to avoid any contraction of sutured tendons during the first month, which is equivalent to avoiding actively removing the arm from the body.
I just want to say that the instructions can be very different from one team to another or following an open surgery.