A linguist studying the spread of new words and slang observed that the number of daily occurrences of the recently popular expression "on fleek" on Twitter (in thousands), as a function of time t in months since the first appearance of the phrase, was well-approximated by a logistic function of the form P(t) = L 1+ Ce-kt where L = 348, C = 86, and k = 60.4%. How many months after the phrase's first appearance was its use spreading most rapidly? Express your answer in months rounded correctly to two decimal places.