Beeper (Beeper Cloud) is a cross-platform stack that supports multiple messaging systems (not just iMessage) and has been in development for years.[1] This is different from Beeper Mini, which is a recently launched Android-exclusive app that only supports SMS/MMS and iMessage.[2]

The release of Beeper Mini certainly gained publicity for Beeper Cloud, and I don't see why Beeper Mini would cause Beeper Cloud to go defunct.

[1] Beeper Cloud: https://www.beeper.com/cloud

[2] Beeper Mini: https://blog.beeper.com/p/introducing-beeper-mini-get-blue