Only after Microsoft promotes the version as suitable for widespread company deployment by marking it as "Current Branch for Business," or starting this fall, as "Semi-Annual Channel (Broad)," are enterprises to roll it out to workers. So the maximum amount of support to businesses for a given version: 14 months.
Even companies that jump on the uneven code -- what Microsoft now calls "Current Branch" but will rename "Semi-Annual Channel (Pilot) in September -- may not get 18 months on a release.
"Microsoft told us, 'Don't install it yet,'" Cherry said of version 1703, the feature upgrade that launched April 11.
He was referring to Microsoft's message, actually aimed at consumers, that they wait for Microsoft to offer the refresh rather than grabbing it immediately.
Microsoft delivers feature upgrades in stages, first to a small set of users whose systems will have the greatest chance of successfully completing the upgrade. The company expands the upgrade pool as it fixes problems reported by others until it opens the throttle.
Last year it took three months to ship 2016's one upgrade to more than 80 per cent of those running Windows 10, meaning that many had 15 or fewer months of support.
"The 18-month count-down starts on the first day," Cherry said about an upgrade's release. "But if you're not at the front of the testing line, you don't get 18 months. So should I speed up my timeline to get [the full] 18?"
If Microsoft promises that support lifecycle, Cherry argued, enterprise users should get it. "The clock really shouldn't start until [a version] is fully deployable without concerns," he said.
That would be when Microsoft reported a build as business ready, and promoted it to the Current Branch for Business, or when that label wears out, Semi-Annual Channel (Broad).
Under that alternate scheme, Windows 10 upgrades would be supported for a total of 22 months, not 18, as each refresh would still require some testing, presumably the same four months as today, with consumers before it's rated ready for enterprise deployment.
Such a change may seem minor, but it would mean -- assuming Microsoft continues to issue feature upgrades at six-month intervals -- that the firm would be required to support not two, but three CBB/Semi-Annual Channel (Broad) releases simultaneously, and for a four-month span when the latest was in consumers' hands, four releases.
To know when support lapses for each given Windows 10 release, enterprises must construct visual aids, Cherry argued. "You have to actually figure out your support," he complained. "You almost have to build a matrix."
Microsoft has provided nothing like that. Previously, that was understandable because Windows 10 releases were on a more flexible schedule.
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