Describe the bug

AE2 version: 8.4.0
Mod List: forge for MC1.16.5, jei(client), world edit mod 7.2.5
Description about the world: Countless AE2 equipment.

The Bug itself:
The [not-yet-full cell] was directly transported to the [slots in the right] while the ME-IO Port is set to [only move the full cells to the right].
All ME-IO Port in this setting behaved like this on this single cell (or its duplication from creative gamemode).
Other settings and other cells are running as expected.
Manually (ME Chest) produced cells with same contents are working as expected.

Nothing had changed when I closed down the save and entered the world again. It went on well again when I restated the game. But wrong cells keeps being produced in the following save!

The Wrong cell:

I guess something is wrong with the ME-IO Port.

How to reproduce the bug

Actually, I'm not quite sure about how I can reproduce the bug.
There are really complicated AE2 based machines in the save, and I can only report the most relative things:
(Maybe I can individually give the save to the administers here? I can't publish it in public since I'm still working on the save)

At first, it only have the sands, and no more sands are allowed to enter the cell, and it's in a ME-drive connected to a ME-IO Por3 with two creative cells extracting cobblestones and stones from the network.
A storage bus was next to the drive, so I moved it to ME-IO Port0 automatically through export bus with fussy cards (by the way, why do I have to use fussy cards though the cells have exactly the same amount of electricity and content? This is unnecessary in 1.12.2 and 1.7.10). I also used redstone card in "redstone pulse mode".
Port0 is connected to a network with few cobblestones and sands. It works all the time, and transfer the its cells to the right when the work is done.
I transported the cell to another ME-IO Port1. Port1 is "transfer items(stones in a creative cell) from network to the cell" and "move the cells when the work is done" (here it works if I set it to "when the cell is full")
Then the cell is transferred to Port2, a port in setting "transfer items(cobblestone only since the network do not accept other items) from the cell to the network" and "move the cell to the right if the work is done".
Finally it's transferred to another Port, port3. This port is connected to a network with limited cobblestones and millions of sands. The port has setting in the picture I posted last night.
The cells should be put back into the driver after it's full of sands, cobblestones, and stones. And then the cobblestones and the stones would be extracted by the two creative cells.

Expected behavior

ME-IO Port should work as the the description says.

Responding to this sentence I've mentioned:
"(by the way, why do I have to use fussy cards though the cells have exactly the same amount of electricity and content? This is unnecessary in 1.12.2 and 1.7.10)"
I think something is really going wrong with the nbt of the cells or something similar.

Additional details

No response

Which minecraft version are you using?

1.16

On which mod loaders does it happen?

Forge

Crash log

none

Thanks a lot for the report. The NBT in particular was very insightful. This happens because of how we detect a cell as "full", which doesn't work well with partitioned cells. #5588 fixes this by using a proper fullness check.