When to Launch a new Romantasy series

Hi everyone! I’m currently working on a new Romantasy series (I’ve since published 15+ SciFi Romance novels) and need advice on when to launch my new endeavor.

Book 1 is ready—Book 2 is with the editor and probably won’t be back until September—Book 3 part 1 first draft is done—Book 3 part 2 not started.

When I asked AI Thomas the best time to launch a new series like this, he tells me with the upcoming September/October (and holiday rush) this is a bad time to go. He suggests either January or May will be better since folks will be looking for new series to read then.

What do you think? Get all the books done and ready to launch next year (I will space them out 45-90 days in between)? Or do start everything in September?

Thanks!😃