For those unable to keep up, Microsoft could point them toward IE11 and its Enterprise Mode, which would presumably be provided with patches as usual. Customers would not need to be running only the latest IE11 update to receive more fixes.
That kind of browser split -- Spartan (or whatever name it's eventually given) on one hand, IE11 on the other -- would match how Microsoft will handle Windows 10: Consumers will receive automatic OS updates, probably monthly, in lieu of occasional upgrades, while businesses will be able to opt for one of two slower tempos.
More information about Microsoft's Jan. 12, 2016, deadline for upgrading to the newest browser for each version of Windows can be found on the company's website.
Microsoft has scheduled a press and analyst event for Jan. 21 in Redmond, where it will unveil the next iteration of the Windows 10 preview. That version will focus on consumer features, and may include the new browser or rendering engine.
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