Factorio Forums

i'm ocd and spaced out the efficiency modules so they're symetric, but when you mark it for upgrade and let bots do their thing the order/position is lost

Thanks for the report. This is currently working as intended. Upgrading entities functions the same as fast-replacing them. That's to say: the logic simply transfers items from the source to the new entity and does not attempt to preserve any specific order of items in the entity.