- Updated markAccountUnavailable function to accept resetsAtMs for precise cooldown management.

- Added email backfill functionality for Codex OAuth connections to improve account information accuracy.

src/lib/usageDb.js

@@ -703,6 +703,39 @@ export async function getUsageStats(period = "all") {
         if (dateKey > (stats.byEndpoint[epKey].lastUsed || "")) stats.byEndpoint[epKey].lastUsed = dateKey;
       }
     }
+
+    // Overlay lastUsed with precise ISO timestamps from live history (dailySummary only has YYYY-MM-DD)
+    const overlayCutoff = maxDays ? Date.now() - maxDays * 86400000 : 0;
+    for (const entry of history) {
+      const ts = entry.timestamp;
+      if (!ts || new Date(ts).getTime() < overlayCutoff) continue;
+
+      const modelKey = entry.provider ? `${entry.model} (${entry.provider})` : entry.model;
+      if (stats.byModel[modelKey] && new Date(ts) > new Date(stats.byModel[modelKey].lastUsed)) {
+        stats.byModel[modelKey].lastUsed = ts;
+      }
+
+      if (entry.connectionId) {
+        const accountName = connectionMap[entry.connectionId] || `Account ${entry.connectionId.slice(0, 8)}...`;
+        const accountKey = `${entry.model} (${entry.provider} - ${accountName})`;
+        if (stats.byAccount[accountKey] && new Date(ts) > new Date(stats.byAccount[accountKey].lastUsed)) {
+          stats.byAccount[accountKey].lastUsed = ts;
+        }
+      }
+
+      const apiKeyKey = (entry.apiKey && typeof entry.apiKey === "string")
+        ? `${entry.apiKey}|${entry.model}|${entry.provider || "unknown"}`
+        : "local-no-key";
+      if (stats.byApiKey[apiKeyKey] && new Date(ts) > new Date(stats.byApiKey[apiKeyKey].lastUsed)) {
+        stats.byApiKey[apiKeyKey].lastUsed = ts;
+      }
+
+      const endpoint = entry.endpoint || "Unknown";
+      const endpointKey = `${endpoint}|${entry.model}|${entry.provider || "unknown"}`;
+      if (stats.byEndpoint[endpointKey] && new Date(ts) > new Date(stats.byEndpoint[endpointKey].lastUsed)) {
+        stats.byEndpoint[endpointKey].lastUsed = ts;
+      }
+    }
   } else {
     // 24h: use live history (original logic)
     const cutoff = Date.now() - PERIOD_MS["24h"];