My experience from auditing suppliers to the Aerospace industry is that the earlier u book first or business class flights the cheaper the cost. The price will get more expensive the longer u wait to book. Just do an airline price check now and watch the prices increase day by day
From what I hear preconditions do not apply for Thai health insurance. I do know my Thai wife took out dead insurance three months before she died and my thai daughter made out like a bandit one month later.