Enormous buying of US stocks during the week to the middle of last week failed to deliver commensurately positive price action. This is the “tell” we have been waiting for. China (both AUKUS and Evergrande) is also relevant in the deteriorating economic and geopolitical outlook. Sell SPX immediately and review over the next 7-10 days, as outlined below.
It probably does not matter so much as long is it isn't very far into the future. They will all be pretty well correlated with each other. However a really short contract is a bad idea as it might expire at an inconvenient moment.