The problem seems related to release 24.0.187 which includes a workaround for an Exact Online bug with (large) companies and the sync API. Release 24.0.187 went into production on May 15 around 20:15 UTC.
This Exact Online bug seems related to upsell of Exact Online Premium. See Ontbrekende Exact Online transacties en data (Dutch only).
The previous release 24.0.185 has been taken into production again, effectively disabling the workaround.
Exact will reset the API limits at 0:00 Saturday morning. After this, the downloads should run again, except for the large companies then again experiencing the Exact Online bug.
Our team will investigate why the workaround caused additional API calls to be consumed and adapt where possible.
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