You wouldn't normally be signed off work unless you had a bleed. I had pp with my first and was put on bed rest at 28w after I started bleeding. Either the placenta will move enough or it won't, it's out of your hands I'm afraid.
I had complete placenta previa but mines moved they say as your baby grows then the placenta normals moves try not to get so worked up about it and follow your doctors instructions everything should be fine
It's usually 4 weeks before your due date. I also have placenta previa I have complete which means the cervix is completely blocked. I'm going in next week to see if it has moved up. Only restrictions I was given was complete pelvic rest ( which means no sexual intercourse) or exercise. Other then that I they have not given me any work restrictions & I'm on my feet all day I'm a nurse. I was told to watch for bleeding & cramping. If my placenta hasn't moved up by week 34 I will be schedule for a c section. Good luck to u. Hope it moves up.