You are not alone in wondering if Peter is giving us a time reference that provides insight into the timeline of creation account. I believe that when Peter's words are examined in light of the context, what we're given is caution against believing that God will not bring an literal end to His creation.
3:3 Know this first of all, that in the last days mockers will come with their mocking, following after their own lusts, 3:4 and saying, "Where is the promise of His coming? For ever since the fathers fell asleep, all continues just as it was from the beginning of creation." 3:5 For when they maintain this, it escapes their notice that by the word of God the heavens existed long ago and the earth was formed out of water and by water, 3:6 through which the world at that time was destroyed, being flooded with water. 3:7 But by His word the present heavens and earth are being reserved for fire, kept for the day of judgment and destruction of ungodly men.
3:8 But do not let this one fact escape your notice, beloved, that with the Lord one day is like a thousand years, and a thousand years like one day. 3:9 The Lord is not slow about His promise, as some count slowness, but is patient toward you, not wishing for any to perish but for all to come to repentance.
The subject of Peters comments were clearly directed against scoffers, who because the end had not come, were teaching that what Jesus taught about the end of all things was purely symbolic, and not literal. I believe that what Peter was saying that God's concept of time is different than ours. I do not believe that this passage was given as a definitive reference to meaure human time against God's time.
Food for thought?