I agree with everybody regarding the mental ability to manage usage timelines to avoid withdrawals (impossible)
I have however tried this before and can comment as a new H user starting this year that has done H as an opiate virgin about 6 times this year so far:
On a physical withdrawal related level i can comment that when i did H no more then 2-3 days straight (lower but nod level doses done nasally) no sleep, no break, i would not not ever have withdrawals, bit if i went 4 days straight or more no break, no sleep, no sober periods in between, i would have minor withdrawals (compared to full blown opiate withdrawals, but no less hateful) which would usually last about 4 days straight before vanishing.
Even those minor withdrawals are the wost experiences of my life and the reason i stick with other drugs (meth) rather even though i love the opiate high.
2-3 three days max seems safe to avoid withdrawals from a purely physical perspective but that definitely doesnt mean that you will be able to stop at 3 days. I only did because thats when the shit i would buy would run out and im usually good at not buying more drugs when im done due to the driving/legal/late at night risks.