possibly because those didn’t incorporate such fundamental changes to the pattern/kit architecture - now e.g. they support Tempo per pattern, this is a fundamental change, the new OS may have to force a re-read and that’s where your not having saved a kit comes into play - it’s no consolation or comfort to know that this is possibly a case of having lucked out before, but the kits do need to be saved within a project before the project is saved, that’s why I wondered if you were rocking single kits (which would have been imho the only conceivable scenario whereby what you described would have made any sense) - Your patterns are loading Kit 1 now (which is an unsaved Kit with default sounds, but it’s the Kit that’s at the heart of this, not the sounds), it’s as simple as that. There is a temporary working state to some aspects of the workflow, you were able to wing this due to your workflow, but if you had ventured towards two patterns using different Kits(sounds) you’d have known much sooner that this wouldn’t work out.
This is a common pitfall amongst other folk assuming kits are saved when a project is, but that’s not what happens, this is down to the fluid way that Kits can straddle patterns seamlessly when edited live. It’s a good system, but needs understanding.
Even saving/exporting your projects would not have helped you here (you really should be doing this for every OSupdate due to the chance of bricking it e.g.) and that’s because if the Kit wasn’t explicitly saved you would simply be saving the default version of that Kit within the project and at that moment the working version of the project would be lost.
This issue would only affect those using your particular workflow who had been unwittingly exploiting the single working kit buffer
I don’t wish to sound like there’s an element of victim blaming here (nothing would hurt me more than losing sounds that I have designed - and that’s why I methodically back those up off the +Drive) but imho there’s nothing fundamentally amiss with the update itself - it’s been unique circumstances (and luck) which have allowed this to work out for you so far - it seems likely that the Elektron devs would know that this reset would occur, but they wouldn’t be expecting anybody to be working solely with unsaved Kits
Of course, some of this analysis could be incorrect, but I just wanted to try to rationalise what has actually caused this crappy outcome for you so that you can be better armed for the future
I’m resolved to better understand some of the little nuances of the ‘working’ buffers