I also received an invitation from OINP on the 23rd of June and did WES authorization the next day. I submitted my application on the 30th and it was moved to assessment on 14 July.
The thing is, whether you authorize WES for a duplicate report to be sent to OINP before or after you receive NOI, OINP will receive the duplicate report electronically while verifying your record from their database.
So, if you have already authorized WES, no need to contact them again or upload any letter.
What is your current status?