Linuxcnc run step by step from line

I see linuxcnc can run step by step and also run from line but everytime i set run from line if i run step by step, program restart at line 0. Is it possible to make linuxcnc run step by step from line X?

I've done this. However, it was the result of a crash and I was trying to skip the part of the program that had been cut.

That required me to insert a few lines before the point I wanted to resume, and then resume instead on the first inserted line.

I had lost my zero, so I had to pull out and re-home, reset the part's zero.

That means that the first inserted line is a move to a safe spot above the XY you wish to resume.
If the feedrate isn't included in the line you want to resume, set it. F
The next line is to turn on the spindle. I--almost--forgot that one when I went to resume. M3.
And the last one is an M0, pause, are you sure you've thought of everything?
(If the line I'm resuming at is a rapid, G0, I'll change that to a G1 F#<notsofast> to see if I was on the right track. You could even do that for a few lines and then put in another F to get back to normal.)

In my way, i created new function to do this by combine 2 main functions in python code:
1. Set new restart line (i found this function in vcp_toggleaction_run) so program will always restart at this line (default start line is line 0)
2. Run step by step.

> 2. Run step by step.

Oh, no, not with 1,000,000+ lines left I won't... ;^) I've got to have some way of telling it, "Okay, looks good, you take over from here."