A protocol renewal goes through the exact same process as a new protocol does, with a couple minor differences.
When you submit your renewal Protocol Application, also submit a Three Year Update Form so we know how many animals you have used in total over the past three years. If you plan on continuing your research with no interruptions, plan on submitting your renewal 2 or 3 months before the expiration date of your active protocol. This way, if the IACUC Committee requests major changes or revisions, you have time to complete those revisions before the expiration date of the active protocol.
There cannot be a lapse between your soon-to-expire protocol and the renewal approval, otherwise all animals must be transferred to the Vet’s holding protocol and all research must cease. So, turn in your renewal in plenty of time to avoid the holding protocol transfer.