Roth 401k and Roth IRA limits

I am planning on setting up my after-tax contribution to the IRS limit to reach $56,000 for 2019. However, I had a question regarding what applies to this limit. If my employer and I contribute $28,500, that would mean that my after-tax amount I would contribute is $27,500. Then I would roll this over into the in-plan 401k roth and leave it there. This would be a full blown mega backdoor roth 401k ira. However, this and previous years I have been doing the "back door" Roth IRA. Effectively, I have been contributing the IRS limit ($6,000 for 2019) for a traditional IRA (non-employer, personal in a Charles Schwab account), then fully converting the cash in the traditional IRA into a Roth IRA. My question is: does this traditional IRA contribution count to the $56,000 limit? I can't seem to find any information on this and I would need to know so I can determine whether I can contribute the full $27,500, or whether it would be $21,500 if I continue to do the "back door" Roth IRA.