If a robot is on its way to deliver something and the destination is destroyed it keeps flying but does not stop to recharge.
So if the destination is a long way away it flies slowly for a very long time.
[1.1.37]robot recharge
Re: [1.1.37]robot recharge
Cannot reproduce. Post a save that lets you trigger the issue and describe exactly what to do, what happens and what you expect to happen instead, see 3638.