Are calendar spreads more effectively used when the front month contract is closer to expiration? so to give you higher theta decay and less exposure to the market (price movement)? For example, if i write a calendar spread: SELL MAR PUT BUY JULY PUT Under what condition is it better to execute this say on Mar 1st instead of wait until a week before expiration to place the trade. Also are there strategies where you do the calendar spread 1 day before front month expiration? then close it immediately the next day?