forum.freeciv.org

U can middle click on unit/tile and see progress.
When u select unit, progress is not lost yet. U can select and give the same order.
If u give another order, then in next turn progress will be lost.

There's also an option to control this: Game / Options / Local client / Interface "Clear unit orders on selection". (Defaults to being enabled; not sure why, probably because that was the historical behaviour.)