Sorry Nicholas, but the latest dev release I see for ATS (we are talking about ATS here...) is 72c4abd which precedes by a handful of hours the latest stable release (1.2.3) I'm using and for which I'm reporting this problem.
If you are referring to the latest Akeebasubs dev release (0029685) which have indeed released yesterday, please note that it gives an error at install time:
JInstaller: :Install: File does not exist /home/mysite/public_html/tmp/install_5237a41131b8a/plugins/akpayment/sagepay/language/en-GB/en-GB.plg_akpayment_sagepay.ini
Totally unrelated and O.T., but I had problems with Akeeba Backup too. I'm not sure if there has been any mistake on my part (can be...), but yesterday afternoon using it to restore my development site to the production site (on line at last!) I found all my files correctly restored but the Joomla data base was at least partly corrupt (for sure the "output" part of some custom html modules) and I had to use a MySQL export/import to correctly restore it to the new site. Please take this with due uncertainty as I've not yet performed more thorough tests and I don't want to disseminate FUD. If this can matter the backup was performed to and restored from an Amazon S3 bucket.
Sergio