Here (https://drive.google.com/open?id=1n_RsD2_GN2t9Xaj3ft8xPrH0fsayqXO2)'s the saved game to reproduce this.
As you load the saved game, the Convoi information dialog is already open so press the "Go to depot" button immediately.
Thank you for your report - I believe that I have now fixed this. I should be grateful if you could re-test with to-morrow's nightly build.
I confirmed that it has been fixed in today's nightly build(#0088b46).
Thank you for fixing this. (´・ω・`)b