How to recover unclaimed depreciation?

I thought I was a saint for reporting my rental income for the two-three bedrooms I was renting to soon-to-be married, between jobs family and friends. I filed a Schedule E for all applicable years, 2020, 2021, and 2022. Now, I have only this week learned of the impending Depreciation Recapture when/if I sell the home. I never claimed depreciation, and I suspect, because I am usually very thorough, and based on a number of other comments and questions in this forum, TT doesn't always prompt you for depreciation, or at least does not do it in a way that's intuitive to someone who is completely ignorant of it (as I was, admittedly). Either way, not here to criticize TT for that. Point is, I never claimed the depreciation for those years. 

 

I can amend 2021 and 2022, but 2020 is out of reach. What are my options for accessing that 2020 depreciation? The internet seems to agree that a 3115 is in order, but my CPA, who I am meeting with in a few days, has been adamant that I do not need a 3115. He is a cagy fellow who communicates poorly in text, so until I sit down with him I cannot truly understand his reasoning. What I can surmise is, if we amend 2021, then we will no longer have "back-to-back" impermissible methods, and therefore no 3115 will be needed...? Idk what else he could be thinking.  And if that were the case, and since I cannot amend 2020, how would I claim that depreciation?

 

Unsure of best course of action here.