Make sure value is always UTC and timeZone is applied to the user input if provided.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@tp/tp-date-input",
-  "version": "2.0.2",
+  "version": "2.0.3",
   "description": "",
   "main": "tp-date-input.js",
   "scripts": {

tp-date-input.js

@@ -308,10 +308,18 @@ class TpDateInput extends EventHelpers(ControlState(FormElement(LitElement))) {
       this.inputs[1].invalid = false;
       this.inputs[2].invalid = false;
       
-      // Convert to specified timezone or use system timezone
-      const finalDt = this.timeZone ? dt.setZone(this.timeZone) : dt;
+      // If timeZone is specified, interpret the entered date values as being in that timezone
+      // and output as UTC. This ensures filters work correctly against UTC-stored dates.
+      let finalDt;
+      if (this.timeZone) {
+        // keepLocalTime: true interprets the entered values as being in the specified timezone
+        finalDt = this.timeZone ? dt.setZone(this.timeZone, { keepLocalTime: true }) : dt;
+      } else {
+        finalDt = dt;
+      }
+
       this.date = finalDt.toJSDate();
-      this.value = finalDt.toISO();
+      this.value = finalDt.toUTC().toISO();
       this.invalid = false;
       this.dispatchEvent(new CustomEvent('value-changed', { detail: this.value, bubbles: true, composed: true }));
     } else {