[Duplicity-talk] Restarting from wrong place

[backup]

Hi y'all. Thanks for this handy tool! I'm running into a problem trying to back 
up about 1 TB to Backblaze B2, using duplicity 0.7.12 on Ubuntu 17.10  (since 
that's the most recent packaged version).

Something has gone wrong in the middle of my backup. There should be 4703 
volumes in the backup, but there are only 4669. When I examine what's actually 
present in B2, I see that the 34 missing volumes are from the middle of the set:

2450, 2746, 3126, 3127, 3128, 3129, 3130, 3131, 3132, 3133, 3134, 3135, 3136, 
3137, 3138, 3139, 3140, 3141, 3276, 3277, 3278, 3279, 3280, 3281, 3730, 3732, 
3733, 3735, 3878, 3879, 3880, 3883, 3884, 3885

duplicity notices that the backup set is incomplete...

> Last full backup left a partial set, restarting.

But then it picks up the backup from volume #4669, not from the first missing 
volume: 

> Found 4703 volumes in manifest
> RESTART: Volumes 4669 to 4703 failed to upload before termination.
>          Restarting backup at volume 4669.

Is there a way to get it to fill in the gaps instead?

Thanks,
Aneel