Should I divide or pot this L. anceps??

[Austin Powers]

I saw mention of the cut part way through technique in another post. In terms of timing, when do you cut part way through?? Do you wait until you see the lead start to grow, or before the lead is really active? The plant I have is growing several roots just under the lead pbulb. With the lengthening days I imagine the lead will become active in the next few weeks.
Thanks for the input,
Stephen