Yes you have a choice. If you use the Desktop program you can switch to forms and the Info Wks part II has a selection to select 1040SR or not. You can not change it in the Online versions. In the Online version if you want to use the regular 1040 form, you can print out the 1040SR and copy the amounts onto the 1040 and then mail your return.
Why don't you want to use the 1040SR?
Even the regular 2019 1040 return is now different than 2018. They changed the line numbers again and reduced the new schedules from 6 to 3.
1040SR https://www.irs.gov/pub/irs-pdf/f1040s.pdf
1040 https://www.irs.gov/pub/irs-pdf/f1040.pdf
