diff --git a/Code/pico_multi_booter/picomite/FileIO.c b/Code/pico_multi_booter/picomite/FileIO.c
index 4c4f2bc..8fed748 100644
--- a/Code/pico_multi_booter/picomite/FileIO.c
+++ b/Code/pico_multi_booter/picomite/FileIO.c
@@ -5484,14 +5484,19 @@ void ClearSavedVars(void)
 }
 void SaveOptions(void)
 {
+    uint8_t buf[FLASH_ERASE_SIZE];
+    // load flash content to buf
+    memcpy(buf, (const void*)(XIP_BASE + FLASH_TARGET_OFFSET), FLASH_ERASE_SIZE);
+    // overwrite the options
+    memcpy(buf, (const uint8_t *)&Option, sizeof(struct option_s));
     uSec(100000);
     disable_interrupts_pico();
     flash_range_erase(FLASH_TARGET_OFFSET, FLASH_ERASE_SIZE);
     enable_interrupts_pico();
     uSec(10000);
     disable_interrupts_pico();
-    // XXX @cuu erased 4K, but only write sizeof(option) back?
-    flash_range_program(FLASH_TARGET_OFFSET, (const uint8_t *)&Option, sizeof(struct option_s));
+    // save flash block back
+    flash_range_program(FLASH_TARGET_OFFSET, buf, FLASH_ERASE_SIZE);
     enable_interrupts_pico();
 }
 /*  @endcond */
diff --git a/Code/pico_multi_booter/picomite/MM_Misc.c b/Code/pico_multi_booter/picomite/MM_Misc.c
index 4f634f2..875962e 100644
--- a/Code/pico_multi_booter/picomite/MM_Misc.c
+++ b/Code/pico_multi_booter/picomite/MM_Misc.c
@@ -4653,15 +4653,7 @@ tp = checkstring(cmdline, (unsigned char *)"HEARTBEAT");
         }
         Option.Magic=MagicKey; //This isn't ideal but it improves the chances of a older config working in a new build
         FileClose(fnbr);
-        uSec(100000);
-        disable_interrupts_pico();
-        flash_range_erase(FLASH_TARGET_OFFSET, FLASH_ERASE_SIZE);
-        enable_interrupts_pico();
-        uSec(10000);
-        disable_interrupts_pico();
-        // XXX @cuu not writing sizeof(option)?
-        flash_range_program(FLASH_TARGET_OFFSET, (const uint8_t *)&Option, sizeof(struct option_s));
-        enable_interrupts_pico();
+        SaveOptions();
         _excep_code = RESET_COMMAND;
         SoftReset();
     }