From http://helsinkiowcup.fi/wp-content/uplo ... etin-3.pdf page 13:
Long, chase start
Start times will be determined by times in the Middle competition, with
the following bonus seconds deducted according to placings in the Middle:
120-90-60-45-30-25-20-15-10-5 for places 1-2-3-4-5-6-7-8-9-10. Published
times for the event will be the sum of the times from the Middle and Long,
chase start, minus any applicable bonus seconds. Placings will be determined
by order across the finishing line for those who start in the true chasing start.