SEP to Solo 401K and backdoor

Hello all,

Today December 30th I had my SEP to Solo 401K conversion done, I see all the stocks, etc in my Solo 401K. My SEP is now $0.00

My goal is to avoid pro rata and perform a backdoor Roth conversion. This is why I did the SEP to SOLO.

I have the funds settled in a newly created traditional IRA ($7k) ready to convert to my ROTH IRA.

Can I do this transaction on the same day as my SEP to SOLO 401K conversion?

Obviously I’m really close to the end of the year here, or should I wait till tomorrow December 31st to initiate the backdoor Roth conversion?

Thank you!!