Last part of the Maha-satipatthana Sutta
"Now, if anyone would develop these four frames of reference in this
way for seven years, one of two fruits can be expected for him: either
gnosis right here & now, or — if there be any remnant of
clinging-sustenance — non-return.
"Let alone seven years. If anyone would develop these four frames of
reference in this way for six years... five... four... three... two
years... one year... seven months... six months... five... four...
three... two months... one month... half a month, one of two fruits
can be expected for him: either gnosis right here & now, or — if there
be any remnant of clinging-sustenance — non-return.
"Let alone half a month. If anyone would develop these four frames of
reference in this way for seven days, one of two fruits can be
expected for him: either gnosis right here & now, or — if there be any
remnant of clinging-sustenance — non-return.
"'This is the direct path for the purification of beings, for the
overcoming of sorrow & lamentation, for the disappearance of pain &
distress, for the attainment of the right method, & for the
realization of Unbinding — in other words, the four frames of
reference.' Thus was it said, and in reference to this was it said."
That is what the Blessed One said. Gratified, the monks delighted in
the Blessed One's words. DN 22
So basically, depends on the individual!