F1 visa approval and travel date


I am a new student and have an I-20 with spring 2021 date (deferred from Fall 2020).

  1. If I get F1 visa approved now with this I-20 but for some situation travel in Fall 2021 (with another deferment and a Fall-2021 I-20 - same university), would there be any issue with travel / CBP at Port of Entry / SEVIS record, etc.?

  2. Will the 5 month rule be applicable in the above case (visa approval date and travel date gap will be clearly more than 5 months)?

  3. Since visa stamp will have program start date as Spring 2021, will the above create any issue when I actually travel later with Fall 2021 start date in modified I-20 ?

Any help will be much appreciated.