How long does it take to process once transmit return button is pushed

It takes roughly 48-72 hours for your returns to be accepted once they are transmitted, then approx. another 21 days for your refund to be released from the date your return is accepted. See below for information on how to track your refund.

https://ttlc.intuit.com/replies/5340655

i filled my taxes on 1/16/2020 and here it is 4 days later and it still says pending. Every other time it was accepted within 24 hours. Im curious as to why this is taking so long 

Not until the IRS opens on Jan 27, 2020 and your return is Accepted.  Until then it will stay Pending on Turbo Tax.

IRS opens on Jan 27, 2020 for 2019 returns
https://www.irs.gov/newsroom/irs-opens-2020-filing-season-for-individual-filers-on-jan-27

But the IRS has pulled some returns early for testing.