Just an Update
Well after lots of trials it does look like this is in the AltUi plugin in OpenLuup, stopping Openluup with
http://RPI_IP:3480/data_request?id=exit
and then SSHing into the pi and reloading it with
./openluup_reload
connects to the Arduino gateway without a problem and without the multiple reload of Luup.
Clicking "Reload Luup Engine" from the misc menu in AltUi always results in multiple reloads 5-10 times.
Changing an attribute of a device in AltUi prompts a single reload of Luup again connecting with the Arduino gateway fine without the multiple reload cycles
regards
Nik