Partial pot-files destroy translations

In the past launchpad kept translations also when the current pot-file did not contain them. So when strings reappeared, they already had their previous translation.

This feature seems to be gone. For JOSM due to a bug in build script the josm.pot did not contain 80 translations. Now after I reuploaded the file the 80 translations are still missing for all lanuages, even for these where they have been translated in past.

This is a major waste of translation power which can be caused by a simple error - imagine e.g. a broken upload containing only one string. Will this cause all 7000 translations to disappear forever?