Yes, the attorney thinks the older child can get citizenship after the 5 year mark - if they remain a dependent, regardless of age. The citizenship would also need to happen while they are a dependent. We have a small chance of that if the time starts at June 2022 for us as my oldest is starting a Ph.D. program in the fall. If he is no longer a dependent at the 5 year mark, then he will still get credit for the years that he was a dependent to be used towards a non-GV citizenship pathway.
The resubmission is required for all that have applied and have not yet had biometrics. We applied June 2022 and have not had biometrics yet so refreshed all paperwork this Feb 2025. I think they are hoping folks will drop out of the line and fail to resubmit.