After several days waiting, apt says it is now safe to do a full-upgrade:
.... qtbase5-dev-tools qtscript5-dev qttranslations5-l10n qtwayland5 rfkill sonnet-plugins svgpart sweeper
systemsettings user-manager util-linux yakuake
482 upgraded, 7 newly installed, 0 to remove and 0 not upgraded.
Need to get 43.7 MB/429 MB of archives.
After this operation, 291 MB of additional disk space will be used.
Do you want to continue? [Y/n]