Yes you can line-up and hold, but I wouldn't consider this to be wise.
There have been numerous accidents over the years with aircraft lining up and holding on the threshold, only to have an aircraft land on top of them.
Safest option is to hold in a position whereby you can see at least aircraft on final, then when clear line-up and roll in one motion. Radio is relied upon far too heavily, it relies on everyone having a serviceable radio, on the correct frequency, a competent operator at the end of it and no over transmissions.
I get nervous when given a line up and wait instruction at a controlled airport and certainly wouldn't do so at a NCTL.