44AD five years block

NO.......... that is not your own choice !!!

Yes from A.Y.18-19 once you opted out of Sec 44AB you cant opt for Sec 44AD for next 5 yeard....

But  had no option to continue 44AD in FY 17-18 as my turnover was more than 2 cr. I was not eligible for FY 17--18. It was not by choice.

Then also you have to opt out of Sec 44AD for next 5 years.....

i think in that year 44ad any which case not applicable becz you crossing the limit of 2 crore

5 year condition in that year apply in which your turnover is less than 2 crore and you shown profit less than 8% in that year you broke the condition

turnover is not in your control but showing less profit is in your control

so for next year you are very much eligible