What’s the cooking time for an Instant Pot?

It usually takes between 45 minutes and 1 hour to achieve a shredable texture in an Instant Pot. You can try the shorter time to start, then release pressure and check your meat. It it isn't shredding and falling apart, close it up and go for another 15 minutes. If you don't have the time to do that, there's no harm in just setting it for the full hour, either.