Service providers need to rapidly move to the next phase in RCS development by commercializing A2P RCS. The early traction of OTT business chat services from Facebook and WhatsApp serves to both validate the investment of mobile operators in RCS, but also highlights the clear threat from OTTs as operators aim to at first protect, and then grow, their stagnant A2P messaging businesses. This insight provides an update of Strategy Analytics’ perspective on RCS and raises key questions which operators must address to remain relevant in messaging.