How exactly are -local.cfg files POSTed to server ?

Hi,

I'm discovering Autop_Protect feature, enabling uploading of -local.cfg files to a provisioning server.

I'm evaluating this feature with T42S powered by 66.82.0.30 firmware.

My settings are:
static.auto_provision.server.url = http://192.168.64.250/yealink
static.auto_provision.custom.protect = 1
static.auto_provision.custom.sync = 1
static.auto_provision.custom.upload_method = 1
static.auto_provision.custom.sync.path = http://192.168.64.250/yealink/001565bffdfe-local.cfg

When I change my Ringing tone using phone display and keys, I can see in my /var/log/apache2/access.log file lines such as:
192.168.64.42 - - [19/Mar/2018:18:06:13 +0100] "POST /yealink/ HTTP/1.1" 404 526 "-" "Yealink SIP-T42S 66.82.0.30 00:15:65:bf:fd:fe"

I would expect "POST /yealink/001565bffdfe-local.cfg HTTP/1.1" 200 as my /yealink/001565bffdfe-local.cfg exists.

Thoughts ?
Can you reproduce this ?

Cheers