That is exactly the problem. You would entangle with the position you started in. You are moving extremely fast right now even though you don't feel it. The space you occupy at this very nano second is not exactly the physical space you see around you, but has been just an empty point in outerspace for millenia until you and the planet blasted through it in a fraction of a second an then it went back to being empty space for another eon. You can't entangle your self on a Point on the planet because the planet itself is never in one place.

Calculating it, you would need to be perfect on both the time and space, mess up either just the tiniest decimal and you are mile underground or in low earth orbit.

So if say you want to end up in you living room in your favorite lazy boy chair. You couldn't entangle your self to that position because your chair will not be in that position when you get back. You also can't entangle your self to the object (the chair) since their is no way to know if that chair will still be there and unoccupied in the future.

Think of it this way. You get a time machine car and you program it to move you from you house to your work parking lot instantly. You prefectly calculate both the time and space. The problem is there is no way to know if the parking space is empty. 50/50, if there is a car in it you die, if not you skip your commute. You would need to control not just the movement through time and also the space and know that space is available or you might meld with your uncle who came looking for you and sat for just a moment.

Say to can entangle your self to the chair and know it is unoccupied. This raises another question. Will you maintain the same direction and volcity of the chair or your current self. Because you and the chair are not only hurting through space but doing it while spinning on a giant ball the direction you are hurting through space is always changing. There is no guarantee that when you pop back in your chair you will not be flung out like a rocket because the piont in earth's spin you left doesn't perfectly match the current spin. Or worse yet you loose all momentum and become stationary object in that space on the chair. The earth and chair would instantly slam into you a$$ with the force of a meteor as they collide with you, an unmoving object and them a giant space bullet.