By harnessing the powers of Data Science™ I would have expected the 1.0 version to be released last week - early morning on February 14th to be exact... 
library(tidyverse)
library(rvest)
dataset <- read_html("https://cran.r-project.org/src/contrib/Archive/dplyr/") %>%
html_node("table") %>%
html_table(fill = T) %>%
select(version = Name, date = 'Last modified') %>%
filter(str_starts(date, "2")) %>%
mutate(version = str_remove(version, "dplyr_0.")) %>%
mutate(version = as.numeric(str_remove(version, ".tar.gz")),
date = as.POSIXct(date, tz = "UTC")) %>%
filter(!is.na(version))
model <- lm(data = dataset, date ~ version)
release <- predict(model,
newdata = data.frame(version = c(10)))
as.POSIXct(release, origin="1970-01-01")
"2020-02-14 05:16:57 CET"