comsec amend order question

Question: I use Comsec. If I have a Sell order sitting in the queue and I amend it by changing the number of units does my order stay in the same position or move to the back of the queue (within the same price).
For example, there are 7 sell orders for the same price, mine is the top (I think). I want to reduce the number of units for sale. If I amend my order does my order position change?
Does the answer vary depending on whether I increase or decrease my number of units?