Opening project in QtC 5 loses previous BuildDirectory for build configurations

I have been using QtC 4.11.0 on macOS 10.14.6.

I decided I should give a more recent version a try, so I also installed QtC 5.0.0.

When I opened my qmake based project in QtC 5, I noticed that the build directory for all of my configurations was lost, and now everything builds in the same directory as the source code. Previously all configurations were shadow builds outside of the source directory.

I quit QtC 5 and restored my .pro.user file from backup. I then opened that project using QtC 4.11.0. The build directories are correct in this version. I made a backup copy of the .pro.user file. I will attach that as IgorPhoenix.pro.user.beforeOpenWithQtC5.

I then quit 4.11 and opened the same project in QtC 5. The build directories are now messed up again. I quit QtC and made another copy of the .pro.user file. I will attach that as IgorPhoenix.pro.user.afterOpenWithQtC5.

I have a lot of different build configurations and I would prefer not to fix all of the build directories by hand. Any thoughts on how to prevent this from happening?

I have not tried any version of QtC between 4.11 and 5. So it is possible that this bug (I assume it's a bug) was introduced sometime before QtC 5.