Apple’s long-rumored Mac ARM chip transition could happen as early as next year, according to a new report from Bloomberg. The report says that Apple is currently working on three Mac processors based on the design of the A14 system-on-a-chip that will power the next-generation iPhone. The first of the Mac versions will greatly exceed the speed of the iPhone and iPad processors, according to the report’s sources.

Already, Apple’s A-series line of ARM-based chips for iPhones and iPads have been steadily improving, to the point where their performance in benchmark tests regularly exceeds that of Intel processors used currently in Apple’s Mac line. As a result, and because Intel’s chip development has encountered a few setbacks and slowdowns in recent generations, rumors that Apple would move to using its own ARM-based designs have multiplied over the past few years.

Bloomberg says that “at least one Mac” powered by Apple’s own chip is being prepared for release in 2021, to be built by chip fabricator and longtime Apple partner Taiwan Semiconductor Manufacturing Co. (TSMC). The first of these chips to power Macs will have at least 12 cores, including eight designed for high-performance applications, and four designed for lower-intensity activities with battery-preserving energy efficiency characteristics. Current Intel designs that Apple employs in devices such as the MacBook Air have four or even two cores, by comparison.

Initially, the report claims Apple will focus on using the chips to power a new Mac design, leaving Intel processors in its higher-end pro level Macs, because the ARM-based designs, while more performant on some scores, can’t yet match the top-end performance of Intel-based chip technology. ARM chips generally provide more power efficiency at the expense of raw computing power, which is why they’re so frequently used in mobile devices.

The first ARM-based Macs will still run macOS, per Bloomberg’s sources, and Apple will seek to make them compatible with software that works on current Intel-based Macs as well. That would be a similar endeavor to when Apple switched from using PowerPC-based processors to Intel chips for its Mac lineup in 2006, so the company has some experience in this regard. During that transition, Apple announced initially that the switch would take place between 2006 and 2007, but accelerated its plans so that all new Macs shipping by the end of 2006 were powered by Intel processors.