The MOD has agreed with the Home Office to extend the time limit before discharge that non-UK Service Personnel can submit applications for Indefinite Leave to Remain, with immediate effect.
Previously, non-UK soldiers had been able to apply for Indefinite Leave to Remain (ILR) up to 10 weeks prior to discharge. This has now been changed to up to 18 weeks prior to discharge.
It will take time to reflect this in Army / MOD and Home Office documents and websites, as well as other Army guidance documents. In the meantime, any questions should be directed to your soldier's chain of command.