[[!comment format=mdwn
 username="https://me.yahoo.com/a/EbvxpTI_xP9Aod7Mg4cwGhgjrCrdM5s-#7c0f4"
 subject="comment 2"
 date="2016-06-09T20:49:53Z"
 content="""
Thanks for the details!  Indeed, IMHO it would be nice to preserve backend for a file, since otherwise I am afraid many 'heterogeneous' annex'es where different files were added manually with different backends (intentionally) would start migrating -- might lead to unpleasant surprises. 
"""]]