As you might be aware, 2019.1.3f1 experienced a lot of build failures recently which could be worked around by switching your Unity target version to 2019.1.2f1. Fortunately I can report that I tracked down what I believe to have been the main cause of these issues and iOS build failures should now be back to normal. This means that you can go back to targeting 2019.1.3f1 if you want, or return to targeting "Always Use Latest 2019.1" versions - which now targets 2019.1.4f1. We have recently had several unexpected breakages from releasing new Unity versions however. We have a few features coming soon to make it easier to detect and avoid breakages introduced by new Unity versions. We'll also be making our testing suite for new Unity version releases more extensive and automatic. If you are still experiencing iOS build issues in 2019.1.4f1 then please feel free to post here or open a support ticket - and if you were previously experiencing issues which went away when switching down to 2019.1.2f1 then it would be good to know if these are now resolved in 2019.1.4f1. Tracking down the replication for this issue was very tricky - although I believe that the majority of new iOS issues should be resolved now, I definitely want to keep a close eye on things and make sure that this has worked for all of our customers.