As per the recommendations on http://www.hoppie.nl/acars/system/tech.html, the polling frequency has been reduced from 1 per second to 1 per minute, randomized to +/- 15 seconds. This is necessary to avoid excessive server load.
As a result, ACARS and CPDLC messages from the Hoppie network may take up to 75 seconds (plus HTTP latencies) to arrive; this, however, is actually realistic.
Please install this update to help keep the Hoppie network accessible for all.