Difference between CHP and Regent's?

I’m wondering the difference between CHP and Regents for UCI. Some of my friends only got regents, with one letter, and some got CHP only with one letter, and some got a letter for both. If they are different, which one is more selective on average? Which prospective majors would it be hardest to get CHP for if this was the case?

Regents is a scholarship that is renewable each year with a GPA requirement. CHP is the Honors program but no monetary award involved, just some great perks. Both are very competitive and selective.

https://www.ofas.uci.edu/content/TypesOfAid.aspx?nav=1&id=regents

http://honors.uci.edu

The people who got Regents letters will probably get a seperate CHP letter. My son got both but days apart.