2Pe 3:2
That ye may be mindful of the words which were spoken before by the holy prophets, and of the commandment of us the apostles of the Lord and Saviour:
2Pe 3:3
Knowing this first, that there shall come in the last days scoffers, walking after their own lusts,
Notice that Peter first mentions "words which were spoken by the holy prophets (i.e - OT prophets) as well as apostles -- so it is indicated that these "words that were spoken before" may be the source of the "there shall come..." idea.
This DOES NOT blow the idea of the OP - that scoffers/cynics were ALREADY PRESENT when Peter wrote -- in fact the preponderance of statements in this chapter and other NT writings does indicate that the cynics were already there -- and it is said of them "they ARE willingly ignorant..." (of biblical creation, etc) - PRESENT TENSE
ARE willingly ignorant - means they ARE THEN in Peter's time - doesnt say "there WILL ARISE scoffers who WILL BE willingly ignorant 2000 years from now..." etc -
it speaks of the cynics' EXISTENCE and IGNORANCE as a PRESENT REALITY
Earlier in ch 2, we see exactly the SAME PATTERN of "future tense about wrong ideas that will come, more info on it which indicates present tense existence already of the things that WILL COME" -
I cannot agree with BW that one or a few future tense refernces IN THE MIDST OF other present tense references that the false teacher and the scoffers ARE ALREADY HERE should blow the idea of the OP
in ch 2, a first reference to the false prophets/teachers in the future tense, but further information that shows that these false prophets/teachers ARE - they SPEAK (presenty tense) - they exist already as Peter writes --
2Pe 2:1
But there were false prophets also among the people, even as there shall be false teachers among you, who privily shall bring in damnable heresies, even denying the Lord that bought them, and bring upon themselves swift destruction.
2Pe 2:12
But these, as natural brute beasts, made to be taken and destroyed, SPEAK (present tense) evil of the things that they understand not; and shall utterly perish in their own corruption;
2Pe 2:13
And shall receive the reward of unrighteousness, as they that count it pleasure to riot in the day time. Spots they are and blemishes, sporting themselves with their own deceivings while they FEAST (present tense) with you;
See? Do you get it? They are FEASTING with the real brethren PRESENTLY - "they - the false prophets/teachers" who were the "shall be" spoken of first, are spoken of later as ALREADY PRESENT -
"spots" on the Agape feasts that were going on already.
Back to ch 3 and the scoffers/cynics idea - and the theme of the already-present PAROUSIA DELAY that Peter speaks of -
2Pe 3:9
The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.
Here Peter is addressing comforting words to "the good guys" in the crowd, offering comforting words that the PAROUSIA DELAY which is a reality
(or rather it was then in early 60's AD) is not to be considered slackness but a blessing; and as we now can see, within a decade the longed-for, long-overdue PAROUSIA did indeed come.
PAROUSIA DELAY was a definite "sticky wicket" in Peter's time; its even stickier if it continued 2000 years - but it's not a sticky wicket if the PAROUSIA actually occurred a few years after Peter's death
The PAROUSIA as a "coming in judgement" still within the "generation that will not pass away" - wherein some things were fulfilled LITERALLY (like the stones not being left one on another) and some things FIGURATIVELY (like stars falling from heaven as a metaphor, like the "elements" of the Mosaic era passing way, etc.
I see no reason to dismiss the OP and the position that the scoffers/cynics already were there when Peter wrote.
I would not be too hasty to dismiss that Peter was talking about present realities to him; I also would not dismiss the Mosaic covenant idea mentioned also.
I have pointed out that this pattern of referring to something that was predicted as "WILL OCCUR" is in fuller light shown to already be there when the writer wrote -- the false prophets/teachers in ch 2 and the scoffers/cynics in ch 3
Hope you can see this