All the music shows take the results from the previous week. This means that for example, M!Countdown on 2nd June takes the results(digital,albums sales etc) from 23-29 May.
So if you start to stream when 'Please' is released on 31 May or during that week 1st-5th June, the digital results will be reflected on M!Countdown(9 June), Music Bank (10 June), Inkigayo (12 June). Because Hyun Joong has yet to release his album so based on his digital sales alone he would not be able to win. However it's important to keep his digital ranking high.
So unless you have two accounts, please save your download for 6-12 June.
Because 1 account can only download the same song once.
If you have more than 1 account, then you can use 1 account for each week.
You can start streaming once 'Please' is out since streaming lasts for a month.