F5 provides a 30-day "grace" period to renew certifications that have already expired. During this time, the certification is still expired and may not be used to satisfy prerequisites; however, candidates may still renew them by retaking the last exam they took to achieve the certification without any penalty. (What is the difference between "Expired" and "Final Renew" dates for my certification?)
If you renew your certification during the grace period, your certification date will be based off of the original expiration date, not the date you renew (Why isn't my renewed certification valid for 2-years from my testing date?).
Let's say you achieved the F5-CA certification on January 1st, 2020, with an expiration date of January 1st, 2022.
If you do not renew your F5-CA by January 1st, 2022, it will expire an no longer be valid. You would no longer be eligible for any 300-level exam that requires the F5-CA as a prerequisite.
However, you would still be able to renew your F5-CA until February 1st, 2022 by taking and passing exam 201, the last exam you took to achieve your certification.
If you took and passed exam 201 on January 15th, 2022, your certification date would still be January 1st, 2022 with an expiration of January 1st, 2024, not January 15th.