aarch64 LEAP 42.3 --> 15: Beta available for RPi-3?

My Raspberry Pi-3B installation of aarch64 LEAP 42.3, 4.4.114-42, is stable, but various components complain about hardware events (video related, WiFi related, mmc related). Unfortunately, that’s the installation I consider to be “production”, as it is on a USB-connected SSD and so has more capacity and (should be) faster.

My installation of TW, 4.14.15-7, on a microSD drive is by comparison both more stable (fewer or no complaints about hardware events) and faster.

I’m considering either switching my LEAP installation to TW or waiting to upgrade LEAP to 15. I see that LEAP 15 is available in beta for X86, but I can’t find an aarch64 version. Does anyone know when it might be available and where I might look for it when it is? I converted that SSD from TW to LEAP last year, when an update to TW failed to reboot, so I’m a little reluctant to go back to TW on that primary system. But TW aarch64 for the RPi3B seems increasingly stable, so maybe it’s a safe gamble.