and, tried very hard to find out about this issue....and well, here's what I've learned:

1-it can take seconds or less for miles and miles of nerves to die. The chemistry of it is, well, beyond my humble brain to grasp. I do admit I'm chemistry impaired tho.

2-It is documented that nerves regrow at the rate of 1/2 to 1 cm a MONTH. About a 1/2 to 3/4 inch under IDEAL LAB situations. Research I've read has no clue at all as to which nerves regrow or how...
I've not found a doc that can explain the process, nor a paper nor a description. They plain old don't KNOW - from all I've read.

My take on it is that IF the 'zeeps' are random, they are regenerating. The 'static' you feel is the nerves calling out to the rest of the nerve world: I'm Here! What do I do now....they have to 'connect' and become programmable or be re-programmed. {Is that a word?}. I tell my self that the latter is always the one 'happening'. Because of that, constant attempts at proper therapeutic exercises is important....to tell existing nerves, and help new ones get and keep an idea in their functioning of YOU.

HOpe this helps! - j

When to worry? When the zeeps get to the point that other function aspects are going 'dead' or plain old don't work. Then you call the doc.