Petitioner appeals from the trial court’s sua sponte dismissal of his petition for a writ of habeas corpus. ORS 34.370(2)(b)(A). We reverse and remand.

On appeal, defendant concedes that the trial court’s stated ground for dismissal was erroneous. However, defendant argues that we should affirm on an alternative basis that, given the sua sponte dismissal, was never raised in the trial court.

We conclude, without further discussion, that defendant’s confession of error is well-founded. Further, we decline to consider defendant’s proffered alternative basis for affirmance. See Frady v. Morrow, 169 Or App 250, 255-56, 9 P3d 141 (2000); see also Jones v. Armenakis, 144 Or App 23, 27, 925 P2d 130 (1996), on recons 146 Or App 198, 932 P2d 99 (1997).

Reversed and remanded.