Usually the heating control sends 4 bytes followed by 1004 bytes. If the controller sends the whole 1008 bytes at once the current implementation gets blocked, because it waits for a second frame.
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Rec nr bytes: 4
Rec nr bytes: 1004
Current time: 1583978520 / 0x5e699818 --- Thu Mar 12 03:02:00 2020
getNumberOfEntries: 69
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Rec nr bytes: 1008
---> Here the SW got blocked
Usually the heating control sends 4 bytes followed by 1004 bytes. If the controller sends the whole 1008 bytes at once the current implementation gets blocked, because it waits for a second frame.