Oh, and the 215’s are probably because those calendars are managed by other apps in nextcloud. Namely, contacts and Deck (the scrum tool).
EDIT: the local calendar on nextcloud is NOT syncing correctly. Well, unless I use vdirsync.
EDIT2: the following log generated on doing the sync with QT debug logging:
SNIP
[D] unknown:0 - have new remote addition: "/remote.php/dav/calendars/poetaster.de/local/97a133c5-3770-464e-a21d-671cbdd2ce47.ics"
[D] unknown:0 - Calculated local A/M/R: 0 / 0 / 0
[D] unknown:0 - Calculated remote A/M/R: 153 / 0 / 0
SNIP lot of data
[D] unknown:0 - "---------------------------------------------------------------------"
[D] unknown:0 - "void Report::sendRequest(const QString&, const QByteArray&)" :Exit, execution time: 3 ms
[D] unknown:0 - "void Report::multiGetEvents(const QString&, const QStringList&)" :Exit, execution time: 4 ms
[D] unknown:0 - void NotebookSyncAgent::sendLocalChanges() "5"
[D] unknown:0 - no local changes to upsync - finished with notebook "local" "/remote.php/dav/calendars/poetaster.de/local/"
[D] unknown:0 - void NotebookSyncAgent::requestFinished(Request*) "5"
[D] unknown:0 - "virtual void Report::handleReply(QNetworkReply*)" :Exit, execution time: 44 ms
[D] unknown:0 - "void Request::requestFinished()" :Exit, execution time: 45 ms
[D] unknown:0 - "void Request::requestFinished()" :Entry
[D] unknown:0 - "REPORT" request finished: QNetworkReply::NetworkError(NoError)
[D] unknown:0 - "virtual void Report::handleReply(QNetworkReply*)" :Entry
SNIP
[D] unknown:0 - iCal data contains 1 incidences
[D] unknown:0 - parsed 1 events or todos from the iCal data
[D] unknown:0 - iCal data contains 2 incidences
[W] unknown:0 - iCal data contains invalid incidences with conflicting uids
So, looks like one day is causing the entire import to fail?