Backup performance has changed - Anybody else see it?

Checking my auto backups I see what used to take 15 to 20 minutes now takes 2. That sounds great but nothing has changed on my site (still using aprox 4GB of storage) so it leaves me to wonder if anybody else sees this change or if the backups are not backing up everything as before?

I am going to try to restore a backup to a separate Linode (if possible?) to check they still work.

Here is my recent backup history…

auto 2017-03-12 10:19:57 2017-03-12 10:22:31 2 minutes, 34 seconds successful

auto 2017-03-11 11:18:22 2017-03-11 11:20:22 2 minutes, 0 seconds successful

auto 2017-03-10 11:19:43 2017-03-10 11:21:56 2 minutes, 13 seconds successful

auto 2017-03-09 11:50:09 2017-03-09 12:10:01 19 minutes, 52 seconds successful

auto 2017-03-08 11:54:51 2017-03-08 12:10:36 15 minutes, 45 seconds successful

auto 2017-03-07 11:52:11 2017-03-07 12:09:38 17 minutes, 27 seconds successful

auto 2017-03-06 11:53:54 2017-03-06 12:10:21 16 minutes, 27 seconds successful

auto 2017-03-05 11:51:58 2017-03-05 12:07:13 15 minutes, 15 seconds successful

auto 2017-03-04 11:55:38 2017-03-04 12:09:54 14 minutes, 16 seconds successful

Anybody else see this change?