In a message dated 2/19/2017 8:06:50 A.M. US Mountain Standard Time,
mouse at 
Rodents-Montreal.ORG writes:
    - PDF/A is [...]
 Those are all good  archival properties!  However, it's also R/O. 
Maybe if you stick  to Adobe's tools.  As demonstrated by this thread,
it's entirely  possible to modify such files, even if the currently-easy
ways to do that  involve a trip through a completely different
representation.
I find  it astonishing that anyone would seriously call any documented
file format  read-only.  (If PDF/A isn't documented, then IMO it's not
suitable for  archival under any circumstances.  But this thread makes
it sound as  though it's documented.)
/~\ The ASCII         Mouse
\ / Ribbon Campaign
X   Against HTML        mouse at 
rodents-montreal.org
/ \  Email!         7D C8 61 52 5D E7 2D 39  4E F1 31  3E E8 B3 27 4B
======================
OK .. (correct me if I am gong in the  wrong direction)  so  the
important thing is that  there is...
- data in a format that is readable by others and a  description of
formats so  if needed a reader can be constructed at a  later date if needed.
-non-commercial tools to access it  or have the ability to modify  the data
in the future  for all of  time.
-a reader/writer can be redone to work under  a new operating system  since
source code is freely available  for it?
....  yea...  makes  sense...
I do  know  what I  do in any given week here  is not  necessary  for the
present  but  for  years and   sometimes lifetimes   far removed  from the
present   moment.
#Ed _www.smecc.org_ (
http://www.smecc.org)