Here is the ZCL Debug output when reading the attributes the first time:
14:59:45:160 ZCL read cluster: 0x0011, attribute: 0x0004
14:59:45:160 ZCL cmd-req nwk: 0x7F4F, profile: 0x0104, cluster: 0x0011 cmd: 0x00
14:59:45:186 ZCL read cluster: 0x0011, attribute: 0x001C
14:59:45:186 ZCL cmd-req nwk: 0x7F4F, profile: 0x0104, cluster: 0x0011 cmd: 0x00
14:59:45:374 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0004, status=0x00, type=0x42
14:59:45:395 ZCL read cluster: 0x0011, attribute: 0x002E
14:59:45:395 ZCL cmd-req nwk: 0x7F4F, profile: 0x0104, cluster: 0x0011 cmd: 0x00
14:59:45:415 ZCL got data for node=0x7F4F, cl=0x0011, at=0x001C, status=0x00, type=0x42
14:59:45:428 ZCL read cluster: 0x0011, attribute: 0x0042
14:59:45:428 ZCL read cluster: 0x0011, attribute: 0x0043
14:59:45:429 ZCL read cluster: 0x0011, attribute: 0x0051
14:59:45:429 ZCL read cluster: 0x0011, attribute: 0x0055
14:59:45:430 ZCL cmd-req nwk: 0x7F4F, profile: 0x0104, cluster: 0x0011 cmd: 0x00
14:59:45:436 ZCL got data for node=0x7F4F, cl=0x0011, at=0x002E, status=0x00, type=0x42
14:59:45:456 ZCL read cluster: 0x0011, attribute: 0x0067
14:59:45:457 ZCL read cluster: 0x0011, attribute: 0x0068
14:59:45:457 ZCL read cluster: 0x0011, attribute: 0x006F
14:59:45:457 ZCL read cluster: 0x0011, attribute: 0x0100
14:59:45:458 ZCL cmd-req nwk: 0x7F4F, profile: 0x0104, cluster: 0x0011 cmd: 0x00
14:59:45:478 ZCL got unsupported status: 0x86 for mandatory attribute
14:59:45:479 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0042, status=0x86, type=0x00
14:59:45:479 ZCL got unsupported status: 0x86 for mandatory attribute
14:59:45:479 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0043, status=0x86, type=0x00
**14:59:45:480 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0051, status=0x00, type=0x10**
** 14:59:45:480 ZCL got unsupported status: 0x86 for mandatory attribute**
** 14:59:45:480 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0051, status=0x86, type=0x10**
14:59:45:481 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0055, status=0x00, type=0x10
14:59:45:481 ZCL got unsupported status: 0x86 for mandatory attribute
14:59:45:482 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0055, status=0x86, type=0x10
14:59:45:500 ZCL got unsupported status: 0x86 for mandatory attribute
14:59:45:500 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0067, status=0x86, type=0x00
14:59:45:501 ZCL got unsupported status: 0x86 for mandatory attribute
14:59:45:501 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0068, status=0x86, type=0x00
14:59:45:502 ZCL got data for node=0x7F4F, cl=0x0011, at=0x006F, status=0x00, type=0x18
14:59:45:502 ZCL got unsupported status: 0x86 for mandatory attribute
14:59:45:503 ZCL got data for node=0x7F4F, cl=0x0011, at=0x006F, status=0x86, type=0x18
14:59:45:503 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0100, status=0x00, type=0x23
14:59:45:503 ZCL got unsupported status: 0x86 for mandatory attribute
14:59:45:504 ZCL got data for node=0x7F4F, cl=0x0011, at=0x0100, status=0x86, type=0x23
As you can see in the lines I marked deCONZ first receives the attribute with status=0x00 (succcess, I guess) but also receives the sama attribute with status=0x86 (which should mean it`s unsupported I think).
Any Ideas on that one?