Looping syntax in ODK v1.16.4

What is the problem? Please be detailed.
do we have do/while loop syntax in the above version of the ODK.
basically what i want to achieve is, whether is it possible to submit an Instance form in the middle of the survey. or can somebody suggest a hack to work around it.
P.S. all my ODK question have required column marked as yes
What ODK tool and version are you using? And on what device and operating system version?

What steps can we take to reproduce the problem?

What you have you tried to fix the problem?

Anything else we should know or have? If you have a test form or screenshots or logs, attach here.

There is no notion of do/while loops in ODK Collect. The best you can do is repeats. See https://docs.opendatakit.org/form-logic/#repeating-questions-and-groups-of-questions.

It is not possible to submit an instance in the middle of the survey without writing Java code. If you'd like to see this feature added please write a new topic at http://forum.getodk.org/c/features describing the high-level problem you are trying to solve and why that feature is needed.

okay.. thanks for your response