Cyclops power cells: order in which power cells deplete

I'm certain the cyclops' power cells deplete one at a time. However, I seem to be having trouble determining which cell depletes 1st. I'm starting to wonder whether or not it might be random and I suspect it also differs if one of the six power cells is absent.

First, it's useful to name the positions of the cells so they are fixed, using (for reference see the image below) 'P' for port 'S' for starboard as well as the numbers 0-2 to indicate distance from the stern with 0 being closest to the stern and 2 the farthest. Using this naming system the six power cell slots will be referred P0-P2 and S0 to S2. Henceforth, the slots themselves will be referred to as power cells since it's them that we're interested in and not the actual game item.

It's likely a new cell is randomly chosen after one has been depleted but otherwise I suspect it behaves as follows:

1. The cyclops has rules which precisely determine which power cell to drain next based exactly on the positions of depleted cells.
2. The game treats empty power cells and absent ones as equivalent and therefore for the remainder of this description I will refer only to empty/depleted cells.
3. If all power cells are depleted then the next non-depleted cell will be the one to be drained.

If anyone can refute or prove some/all of these claims it would be much appreciated!

P.S. If you're uncertain why I named the cell slots if I never mention them it's simply because someone might've noticed a set sequence in which cells are used and this allows them to unambiguously describe it.

Solution 1:

Power cells deplete in the order they are inserted. If you remove one and replace it, this one will go to the end of the list.

They charge in the reverse order, so the first to deplete will be the last charged up using the thermal regeneration module and the last one depleted will be the first charged.

(tested during many hundreds of hours of play)