Lately I was having great difficulty in completing backups on my TC - they took forever with many alerts about connection errors. I was finally able to get one good backup of my old Mac with which to restore to my new Mac, but it took 3 days to back up and 3 days to restore! I replaced the original 3TB TC Barracuda drive with an Ironwolf 8TB, and following the instructions in this article along with a Youtube video, it went exactly right. I did have to trim the rubber blocks and perform a quick erase in Airport. However, after initially getting hourly backups just fine and also backing up two other Macs to the same TC, I noticed that a week or two of older backups from my new Mac were suddenly missing. And this morning I saw an alert about a connection error. Rebooting the Mac got it backing up again, but In case it's of interest, my TC backup issues didn't entirely disappear with a new HD. My new Mac is an Apple M2 Max running Sonoma 14.5.