No time is actually too late when it comes to bitcoin investment, if you have your discretionary income ready you can get started and start accumulating Bitcoin instead of waiting more further to avoid more buying opportunity, if you don't understand what discretionary income is then this is what it means it is your leftover fund after you have sort out all necessary important needs so the income left is your discretionary income if you know you don't have discretionary income there is no need going into bitcoin investment because you will definitely see out in shorter period of time because you weren't investing with the amount you can afford to loss.
You can use the DCA strategy to accumulate Bitcoin since it will enable you to accumulate Bitcoin gradually and regularly either weekly or monthly irrespective of the price of bitcoin.