Actually John and Victor's posts bring up a slightly different way of looking at this. I was about to say 'there's nothing stopping anyone skipping a core release for upgrades so they get their own two year cycle', but then I realised that I have a couple of 4.7 sites I'm planning to upgrade directly to 6.x, but need some 6.x versions of modules that aren't quite there yet - and 4.7 is officially past end of life. So obviously you can do it, but scheduling is tight, and if I was actually being paid for these two sites I might not have that option.<br>
<br>It's been mentioned a couple of times on irc, so I can't take credit for the idea, but would it be worth discussing an extension of support for older core versions? To play devils advocate this would mean maintaining 5.x until 8.x is released (or 6.x until 9.x etc.), even if only for security. Obviously contrib support for older (and newer) versions of core remains entirely optional per maintainer/project.<br>
<br>Going by a one year development cycle, and a 6 month contrib/site upgrade period, that would increase the usable lifetime of x version of drupal from ~18 months to ~ 30 months - and it'd do so without any slow down in actual development - although there's clearly non-trivial resources involved in 12 months additional maintenance of a core release.<br>
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