Colorado Residency Rules and Colorado Form 104PN

Consider a retired taxpayer who owns a home both in Colorado and in another state. S/he votes, claims a homestead exemption, and registers his/her car in the second state, and maintains a driver's license in the second state.  All children, now adults, live independently outside of Colorado.  One is a student who was raised in the non-Colorado home and continues to list that residence as a permanent address.  No homestead exemption is claimed for the Colorado home. All taxable retirement income for the year (a Roth in plan conversion from a 401k/403b/457b/traditional IRA) occurs when the taxpayer is at home in the second state.  The taxpayer has elected to wait until s/he is 70 to collect Social Security, and thus has no monthly Social Security income. The taxpayer returns home to the second state  frequently, typically once a month, but in aggregate s/he spends greater than 6 months in residence at his/her Colorado home. Throughout the year, the taxpayer takes non-taxable Roth distributions which are not treated as taxable on a federal return, and hence are not treated as taxable income in Colorado either. The taxpayer does not rent his/her home during the time s/he is out of state.

1) Is the taxpayer required to file a Colorado return, either as a full-year or part year resident?
2) If s/he files as a Part year resident, how does s/he complete Colorado Form 104PN question 1 which asks the start/end date of Colorado residency? TurboTax will not let a taxpayer file 104PN as a part year resident if the entire year is selected.


REFERENCES:
https://tax.colorado.gov/individual-income-tax-filing-requirements

https://tax.colorado.gov/sites/tax/files/01.2021_ITT_Part-Year_Residents_Nonresidents.pdf

https://www.sos.state.co.us/CCR/GenerateRulePdf.do?ruleVersionId=9997&fileName=1%20CCR%20201-2