As far as law is concerned that speculative income is a business income and should have been a part of your tax audit report.
Practically professionals don't agree to revise the tax audit report as it can attract assessment also, however the most correct method is to revise tax audit and include it in the business turnover and profit.
Alternatively, if your CA is suggesting you to show it as no account case, you can do that also but rather than doing that I would recommend to show it as separate business and showing it as normal profit rather than no account case.
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