With iOS 14 already out, it can’t be too long now before Apple releases macOS 11.0 Big Sur. Should you upgrade as soon as you can, hold off until next year, or give it a miss altogether? This article offers some suggestions which you might like to bear in mind.

Catalina has surely proved one of the least popular versions of macOS in recent years. Some users are hoping that Big Sur will wave a magic wand and make the problems in 10.15 go away. They don’t, and they can’t, at least not the major issues which you need to address if you’re going to upgrade to Big Sur. These are:

• Loss of access to 32-bit apps.
• Loss of 32-bit QuickTime codecs and features.
• Inflexibility of System volume and root volume structure, which increases with Big Sur’s SSV.
• Augmented privacy and security.

The best solution to the first two is likely to be in virtualisation, setting up a Virtual Machine to run macOS Mojave, perhaps, using Parallels Desktop, VMware Fusion, or a similar product. You need to do that, and satisfy yourself that it’s working well, before making any decision about upgrading to 10.15 or 11.0. The other two issues aren’t soluble as such, but there should by now be good workarounds for anyone used to adding top-level directories, and the like.

Catalina 10.15.6 does still have problems which are affecting users, which we all hope that Big Sur will address. Among the most serious are:

• Time Machine backup failures.
• Mail data loss.
• Cover art and other issues with Apple’s new media apps.

Unfortunately, bundled apps generally get less thorough beta-testing, and there are seldom the sheer number of users to provide any good indication of whether Big Sur will address each of those.

At least some of the issues with painfully slow Time Machine backups have been resolved, in that macOS 11.0 shouldn’t now try to back up the versions database, which is a recognised cause of problems in Catalina. Others may be fixed by changing storage for your backups to a dedicated APFS volume and using this new feature in Big Sur. However, this is the first version of Time Machine with this major change, and its robustness remains uncertain. If it’s free of significant bugs, it could prove a big step forward for all using Time Machine. Its major disadvantage, though, is that it’s not backward-compatible.

The serious bug(s) in Mail, and those in Music and TV, will now almost certainly never be fixed in Catalina, which should only receive security updates in the future. When Apple does address them (if it hasn’t already), it will be in Big Sur.

One issue which hasn’t gone away altogether, but Big Sur accommodates better than had been expected, is the need for old kernel extensions. At one time, it was feared that this upgrade wouldn’t allow any third-party kernel extensions to be installed, but that isn’t the case, at least not in this first release. As with all major releases of macOS, if you’re reliant on third-party hardware or software which needs a kernel extension, tread cautiously until you are confident that yours are thoroughly compatible.

I have looked at some of the other problems which could arise with Big Sur in this summary. Of those, perhaps the most significant to anyone considering whether to upgrade early are the potential issues with trying to run a dual-boot system, so that you can drop back to an earlier version of macOS when you need to. Dual-booting started to become more tricky with the release of APFS in High Sierra, and each subsequent version of macOS has made it less reliable.

I’ve been dual-booting one of my Big Sur test systems for almost three months now, and it hasn’t been a smooth experience. Some changes in the file system and of course Time Machine don’t work out so well when viewed from Catalina, so if you are going to give this a try, you’ll be better installing Big Sur on a different disk rather than trying to share one with an earlier release of macOS. At least for the betas, the general advice has been that, if you must install Big Sur on the same disk alongside other versions of macOS, put it into its own separate APFS container. However, that has its disadvantages, in that containers don’t share free disk space, forcing you to allocate fixed amounts of storage to each.

Predictably, most discussion and criticism of Big Sur has concerned its radically changed human interface. I’ve been using Big Sur betas in both appearance modes, and am broadly neutral on these changes. For anyone who spends significant time working on iPads and iOS devices, they will undoubtedly integrate better with those. In some specific cases, macOS users will find some of the changes jarring or objectionable, but there are already customisations becoming available which should let you change what you most dislike. Here I single out Frank Reiff’s Boring Old Menu Bar as an excellent example of what is already shipping.

Looking back at previous Mac interfaces, I suspect that most users will come to enjoy using this new design, and that remaining rough edges will get smoothed out in updates. But if you’re more traditional in your tastes, it could infuriate.

As with Catalina, whatever you decide to do, you really don’t want to find yourself having to downgrade to an earlier version of macOS. Doing so is fiddly and takes a great deal of time, more so than previous downgrades, because of the architectural changes that come with Big Sur. Deciding to upgrade isn’t a one-way trip, but finding your way back isn’t something you should wish on yourself.

Finally, your decision is going to be greatly influenced by the version of macOS that you’re currently running. If that’s Catalina, then you’ve already gone through its traumas, and in most cases Big Sur is the only way ahead. The question then is whether to upgrade immediately, or wait until the initial bugs have been addressed in its first updates.

Coming from Mojave and earlier will prove a more substantial shock. With good planning and preparation, though, there’s no reason that it should be dangerous. What is most important is that, no matter how much better Big Sur might prove than Catalina, upgrading isn’t to be taken lightly. Next week I’ll look at how to plan your upgrade to minimise risk and maximise benefit.

PS If you’re running High Sierra, don’t forget that with the release of Big Sur, your Mac will no longer get any security updates.