This is not from Duolingo, but from Kwiziq. It's language related anyway, so I hope it's welcome.
There are some more examples in the lesson:
https://spanish.kwiziq.com/my-languages ... /view/8246
The thing with these kind of sentences is: I would want to insert a negation, which is probably because I'm subconsciously parsing it to andando, [para] que no lleguemos tarde.
Any tricks, anything I could replace para with that would make it more logical without a negation?