In latest roadmap it was newer scheduled for 10.3, but for some 10.3.x update
Android 64bit is scheduled for 10.4
AFAIK, this roadmap as far as those compilers are concerned is still valid.
When exactly any of those releases will actually hit the road, anyone's guess is as good as mine.
macOS 64-bit is needed not just for developing macOS apps, but also internally for iOS development toolchain and supporting iOS 11 and iOS 12 simulators.
Last year, there was public beta for Delphi developers on active subscription that allowed publishing Android applications built with beta on Google Play store. If nothing else similar scenario can be expected for Android 64 bit compiler. I know this is far from ideal... but...
To be on the safe side... anyone should prepare for the worst and release any major updates before August deadline...