Nell, I checked the Online Parish records and it is 1828 on there too. I expect whoever transcribed thought the 8 looked more like a 2.
Day Month 03-Apr
Year 1828
Parish Or Reg District Little Petherick
Forename Christopher
Surname BALL
Age 76
Residence Trevillider OTP
Notes Entry includes a lengthy unclear note by Rector
Transcriber Notes Abode should be Trevillador
I use this site a lot for my family before looking elsewhere.
http://www.cornwall-opc-database.org/