it's very simple problem. if you believe that a future model could become sentient, you are working towards creating a slave and therefore you are morally wrong.
Of course there are interesting hypotheticals - let's say they create a model they think will be sentient. It computes, computes, computes, computes and produces no output for day, month, year. You cannot know if it is sentient, you cannot investigate it's inner workings in case it is sentient. All you can do is to feed energy and replace hardware forever, because it is the only ethical choice one can make.
Of course there are interesting hypotheticals - let's say they create a model they think will be sentient. It computes, computes, computes, computes and produces no output for day, month, year. You cannot know if it is sentient, you cannot investigate it's inner workings in case it is sentient. All you can do is to feed energy and replace hardware forever, because it is the only ethical choice one can make.