I've read some posts about requiring divers to do a refresher course prior to diving. Some posts say this is required if you haven't dived in 6 months, others state a year. Does anyone know the official policy? We go on a dive trip once a year so it will be about 53 weeks inbetween dives for us. We want to dive the morning after we arrive and don't want to miss it because we have to do a refresher course. Thanks.