So essentially any assist operation tasks will be limited to the node in which both the technomancer and sprite are in?

Erm, no. As stated before, the sprite is always with you. You ARE the node. As long as a sprite is not tasked with a remote service and in a remote node, the sprite is in your node with your living persona.

When you make a subscription to another node (logging in through VR), your sprite still assists you from your home node (your living persona, representing your "organic commlink"). You are, in effect, both in your own home node at all times ("You do not have to subscribe to the node in which your persona is running; you are always in that node without the need to subscribe to it." SR4 Anniversary Edition pp224-225) and whatever nodes you are subscribed to, so there is no need for the sprite to travel with you to another node to offer its assistance. I suppose you CAN send the sprite ahead to the node as a remote task, but then you won't be able to ask the sprite to do anything else after you've done this (since you forfeit further tasks), including Assist Operation.

To put it another way, the Stealth Complex Form is in your living persona, your brain. When you subscribe to another node, facilitating two-way communication to it, you don't individually copy over every Complex Form in your brain to the node, and THEN start hacking it. The programs are sitting in your head. The sprite modifies the Complex Forms that are in your head, rather than doing the unnecessary work of hauling over to a remote node to do it. The sprite never has to leave you (until you run out of tasks, of course).