Thank you for posting your query on Microsoft Q&A, from above description I could understand that you are looking for advisory on extending lifetime of refresh token for web apps.
Please do correct me if this is not the case by responding in the comments section.
As per Refresh and session token lifetime policy properties
Refresh and session token configuration are affected by the following properties and their respectively set values. After the retirement of refresh and session token configuration on January 30, 2021, Microsoft Entra ID will only honor the default values described below.
If you decide not to use Conditional Access to manage sign-in frequency, your refresh and session tokens will be set to the default configuration on that date and you'll no longer be able to change their lifetimes.
Any changes to this default period should be changed using **Conditional Access.
Kindly follow Configure adaptive session lifetime policies to manage the lifetime of the refresh token.
Update1:
The refresh token is used to obtain new access and refresh token pairs when the current access token expires. If a user signed in on January 1st, 2024, the refresh token will be valid until 30 March (90 days). If the refresh token is used and the token is refreshed on February 1st, does the app get a new refresh token that is valid until the end of April or until the end of March (same as the first sign-in)?
Once used to get a get a new access token and refresh token the new token will have validity of 90 days.
Please "Accept the answer (Yes)" and "share your feedback ". This will help us and others in the community as well.
Thanks,
Akshay Kaushik