Clarification on Eligibility Date for Settled Status Application

[stonecold]

I would like some clarification regarding my mother’s application for Settled Status.

She arrived in the UK on 25th October 2020 and has been continuously living here since then. Her current biometric residence card is due to expire on 20th November 2025.

Could you please confirm whether she must complete the full 5 years of residence (i.e., from 25th October 2020 to 25th October 2025) before submitting her application? Alternatively, would it be acceptable to apply slightly earlier—for example, around 25th September 2025—given that decisions may take more than a month to process?

I would be grateful for your guidance on the correct timing to ensure her application is valid and does not affect her status.