JAKARTA, Jan 31 (Reuters) - Indonesian insurance rules that come into effect on Feb. 1 are causing huge coal supply backlogs, with dozens of ships held up outside ports unable to load as authorities start checking to see if vessels are in compliance with the new policy. A regulation issued in August last year requires Indonesian exporters of coal and palm oil to use local insurers from Feb. 1, and also requires them to use local shipping companies from May 2020. Indonesia is the world’s...