Folks may be interested in reading what Interlux advised in response to my inquiry.? Sounds like the window is a open a bit wider than a strict application of the "thumbprint" test would suggest --- <<Good Afternoon, When working in temperatures between 80-95F the InterProtect 2000E can certainly begin to cure quite a bit quicker then originally expected. Originally we recommended to wait a minimum of 3 to a maximum of 5 hours before applying your bottom paint. Now we are recommending waiting a minimum of 1 hour and no more then 5 hours. As long as the first coat of ACT was applied between 1 and 5 hours then there will be no adhesion issues. If you wish to give the InterProtect a light sanding if the overcoat window was missed, you can certainly do so, however you will most likely receive a light bond. The thumb print test is a always a great option to go by as well. Thanks, Jay at Interlux Technical Service>>