The syntax of sata_remap is wrong.
Look at my user_config:
{
"extra_cmdline": {
"vid": "0x0951",
"pid": "0x1603",
"sn": "XXXXXXXXX",
"mac1": "XXXXXXX",
"mac2": "XXXXXXX",
"netif_num": "2",
"sata_remap": "24\\>2:25\\>3:26\\>10:27\\>11:28\\>12:29\\>13"
},
"synoinfo": {
"maxdisks": "24",
"esataportcfg": "0x0000",
"usbportcfg": "0x0000",
"internalportcfg": "0xffffff"
},
"extensions": [
"jumkey.acpid2"
]
}
And it's working fine with 24 HDDs from 1 to 24 ordered.