Discussions about Farm Cash

[barbaraelwart]

Hope someone can answer this for me. When you get a request to boost a train it either a) works and you get bonus b) tells you the train cannot be boosted anymore because it is already one day ahead of schedule or c) tells you the trains has already returned to its owner.

These were the only 3 options I thought, but now several people have told me that they are getting 'this request has expired', and now this morning I have several that say that.

I was under the impression that the request could not expire, and was valid until either the train had 12 boosts or it returned, both options covered by other comments. Is this an issue at the moment or does the offer expire, and if so after how long??