about section 44AD ITR4S

No restriction in continuation of filing u/s. 44AD.

But if not filed in any particular year by your own (before five years), then there is restriction for mandatorily non filing (u/s. 44AD) upto next four years.

As per sub section (4) of 44AD

If you are opting for presumptive scheme, you must

File presumptive scheme for atleast 5 years in continuation
If you decide to show and file profits as per regular business  before the end of these 5 years, you will lose presumptive benefits and disallowed from presumptive taxation for the subsequent 5 years. (5 years shall be counted starting the year in which you first file usual taxes for such business).

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