Prorated pricing lets you purchase an Upgrade at discount if you have purchased the prior version in the past year. The calculation is simple. If you purchased half a year ago, you get half off Upgrade pricing. If you purchased four months ago, you get two-thirds off. If you purchased less than three months ago and Upgrade is free with Buyer Protection.
Big Business 13 was a surprise. We built it and set it aside hoping Big Business 12 would work on macOS Big Sur, which it should, but it doesn't. This is a shame because Big Business 12 works with all computers new and old, except for new Macs shipping after November 11, 2020.
Big Business 12 will continue with Updates just the same. But, it will probably never work on macOS Big Sur or new Macs with Apple Silicon. It crashes on Quit which can cause data loss.
Big Business 13 does run on macOS Big Sur and new Macs with Apple Silicon. It also requires a minimum of macOS Mojave or Windows 10 on all computers. Prorated Protection helps you move to the version that works best for you.
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