Transferring Older Time Machine Backups to a New Drive and Which Format to Use For New Time Machine Backups Drive

I strongly advocate obtaining at least one additional backup drive and starting a new set of backups on it. Add it to Time Machine, which will back up to as many devices as you wish to provide for its use.

When you are satisfied that you no longer need backups from a few weeks, months, or years ago stored on any particular backup drive, erase it and start a new set on it. Repeat that cycle in another few weeks, months, or years for the other backup drives. That way, you will never be without at least two alternatives to restore any particular file or an entire system.

sccfromsocal wrote:

Could I copy the older time machine backup drive contents to an SSD formatted as mac OS journaled, store that ssd disk away, and then start fresh with a new SSD formatted as APFS for my newer backups going fore ward?

That old TM backup is already on a HFS+ journaled formatted drive. Just store that away.

I am also wondering if I will actually ever really need all those older backups. If I am gong to a new machine, and want to load apps from a time machine backup, I would probably favor the newer backups, that reflect my most current situation.

Newer Macs won't support 32-bit applications or older incompatible 64-bit applications that reside on those old TM drives. Future use is a good question. I have a bunch of TM drives from previous operating systems here and almost never have a need to use them.

I do not think I will be using any older macs or pre-sierra macs in the future. Even my older mac, has high sierra on it.

It is a good idea to keep a pre-Catalina (e.g. Mojave or older) Mac around for older 32-bit software that you may need. I keep an old 2013 iMac with Mojave on it for just such an occassion, though I also have another newer iMac running Ventura and Parallel's Desktop Pro with that same Mojave guest, so it is redundant.

For my new current time machine backup SSD, I am leaning towards using APFS, but in disk utility, there are 4 different version of APFS. Which one should I use?

Use APFS or APFS case-sensitive. In either case, Time Machine will use it as an APFS case-sensitive drive. Don't use an encrypted TM solution unless you want an all day sucker for backups.

sccfromsocal wrote:

I would like to transfer all my older time machine backups to a newer bigger capacity SSD drive that I will be using as my new time machine backup drive.

We may no longer do that with recent operating systems including Mojave, which obviates your other questions. You are welcome to try it (I have) but I have not found any solution that works. Exactly which operating system ended that ability escaped my notice, but it may have coincided with the advent of APFS.

Here is some context: Copy Time machine backup drives and retain old backups. - Apple Community

You did not specify the operating system for which you want those backups to apply. If you are using an older operating system such as Mavericks this old, archived Apple Support document would be applicable: Transfer Time Machine back-ups from one back-up disc to another (Archived) but my preferred method was to use Disk Utility's Restore function: Restore a disk using Disk Utility on Mac - Apple Support.

But... neither one works any more, at least the last time I tried. I don't want to dissuade you from confirming that for yourself though. It's a time-consuming endeavor.

The new Mac will expect the new Time Machine drive formatted as APFS, which is not compatible with your older Time Machine drives' HFS+ journaled drives backup organization. Put those older TM drives in a safe, fireproof location, and concentrate your new Mac's Time Machine backups on the new drive.