[Bug-ddrescue] Question about 2nd run on same disk with bad sectors on source and new log file

[michalpl7]

Hello,

I did 1st run:

ddrescue -f -g -n /dev/sdb /dev/sda /mnt/rescue1.log

And it finished with:

current pos:   160041 MB,  current status: finished
domain size:   160041 MB,  in    1 area(s)
    rescued:   157140 MB,  in 136256 area(s)  ( 98.18%)
  non-tried:     2900 MB,  in 136255 area(s)  (  1.81%)

    errsize:         0 B,  errors:       0  (  0%)
non-trimmed:         0 B,  in    0 area(s)  (  0%)
  non-split:         0 B,  in    0 area(s)  (  0%)
 bad-sector:         0 B,  in    0 area(s)  (  0%)

And later I run this command again ( with new log file ) on same disks ( 
/dev/sdb is getting bad sectors ) - I know it's my mistake and I should stay 
with 1st run:

ddrescue -f -g -n /dev/sdb /dev/sda /mnt/rescue2.log    // new log file used

My questions:

1) Does ddrescue overwrite data on /dev/sda (target) if it can't get it ( bad 
sectors ) from /dev/sdb or data from 1st run will remain on target drive?
2) Does ddrescue overwrite data on /dev/sda (target) if I didn't specify log 
file from 1st run ( create new one )?
3) If answers to questions above are YES then I understand that it copy this 
new run in same place ( sectors ) as 1st one so I can put it together in data 
recovery application?

Greetings,
Mike