I usually start with 1 layer for hollows or 3 layers for wedges, removing a layer until I end up with 1 layer on the 1k stone.
After 1k I change the tape and move on but I do not change any more.
I mo when you go up the grits the tape wear is minimal (may be this varies depending on which stones are used I do not know).
I have also tried the Duck Tape electrical and I find it is pretty much identical to 3M stuff but cheaper.