ATIH splits up multi-version backups when reconnecting external USB3 HDDs

Hello Forum members,

SHORT: my issue is with ATIH splitting up multi-version backups into multiple separate single-version backups when I reconnect an external USB3 hard disk (backup target).

DETAILED: please help me on an issue I'm having with my ATIH2012(PlusPack) when working with external USB3 hard drives. I run on Windows 7 64 bit; ATIH, OS and HW patched and up to date on latest levels.

I have a daily backup schedule working with an external eSATA HDD (always-connected). This is running reliably.

In addition, I make occasional full backups to an external USB3 hard drive. In fact, it's a PAIR of external USB3 hard drives where I always keep one off-site, far away (Disaster Recovery!).

Despite these two USB3 disks being identical models, Windows for some reason will not assign them the same drive number when connecting them individually, as it would when connecting USB sticks; so I've assigned the HDDs to drive letters X and Y respectively. Only one drive is connected at one time (using the same port and cable). When I switch drives (to be sure I don't break anything even though this could be done online: power off system, switch drives, power on system) Windows correctly recognizes the drive and displays it as X or Y, whichever it is.

I have set up two ATIH backup plans ("PlanX" and "PlanY") to manage these drives (since a plan cannot handle a moving backup target). They are both set to run on demand. The idea is that I trigger the respective backup entry which fits the HDD which happens to be connected to add a full backup version to it, on demand. Ideally the plan would keep versions and delete older versions as the disk fills up. The versions are denominated in format "PLANNAME_HOSTNAME_YYYY-MM-DD", every file on the disk is named in this way, but in ATIH all are displayed as members of the one "PlanX" or "PlanY".

HOWEVER, when I reattach a disk (with previous backup versions on it) and start the plan for a new backup to be added ATIH splits up all previous versions it finds on the disk into SEPARATE backup plan entries!!! The original backup plan (e.g. "PlanY") stays there with only a single version, the current one! The others are down the list with their respective date added to the name (e.g. "PlanY_HOSTNAME_2014-06-24.tib", including ".tib" added to the plan name!), each one with one single version to it! Thus, a backup chain with 6 versions would end up as six individual plans!

What's worse: I now have to watch disk contents and delete old and obsolete versions manually.

?? Why does ATIH not recognizes the backups on disk are connected under one plan?

?? What do I need to do to to make my setup work as I expect it to?

I fear this has nothing to do with ATIH2012 being obsolete, I don't need the features of newer AITH releases and am loath to update at a cost, only to have Acronis support look at this issue and possibly have no solution, so I turn to you first for an assessment.

Maybe I'm doing something wrong or not doing something that would make my plan work!

I have done researche in the help file and searches on the forums and FAQs, but did not find anything related to multi-version splits or external HDDs that could help me.

Thanks for any pointers or advice! Even RTFM are welcome as long as I'm told where to look!

ITALIA (I Thank A Lot In Advance)
Akebinko