lnd ignores update_fee on new connection?

[rustyrussell]

I funded a channel with 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf (Zap Technologies) which seems to be an lnd node based on its features.

We create the commit tx at low feerate (1006):

0200000001d1051af7c4e2218cf21f1b450015148f134626cf4018fcc1580d898157dbc41501000000000e5f108001683f0f000000000016001456c9b57de7610ed4a7721cb5a7797e13ce53d9f47e5a5c20

All goes well, funding tx gets mined and we exchange funding_locked:

channeld-chan#17314: peer_in WIRE_FUNDING_LOCKED
channeld-chan#17314: peer_out WIRE_FUNDING_LOCKED

Then we immediately send update_fee (3767), followed by the signature on the updated tx:
0200000001d1051af7c4e2218cf21f1b450015148f134626cf4018fcc1580d898157dbc41501000000000e5f10800199370f000000000016001456c9b57de7610ed4a7721cb5a7797e13ce53d9f47f5a5c20

channeld-chan#17314: peer_out WIRE_UPDATE_FEE
channeld-chan#17314: peer_out WIRE_COMMITMENT_SIGNED

LND rejects it, using a tx with the old feerate:

0200000001d1051af7c4e2218cf21f1b450015148f134626cf4018fcc1580d898157dbc41501000000000e5f108001683f0f000000000016001456c9b57de7610ed4a7721cb5a7797e13ce53d9f47f5a5c20

Complete logs below:

2019-12-13T06:07:06.998Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-connectd: Connect OUT
2019-12-13T06:07:07.001Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-connectd: peer_out WIRE_INIT
2019-12-13T06:07:07.224Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-connectd: peer_in WIRE_INIT
2019-12-13T06:07:07.310Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: pid 17015, msgfd 56
2019-12-13T06:07:07.318Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-gossipd: seeker: disabling gossip
2019-12-13T06:07:09.746Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: Handed peer, entering loop
2019-12-13T06:07:09.871Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: peer_out WIRE_OPEN_CHANNEL
2019-12-13T06:07:09.979Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: peer_out WIRE_GOSSIP_TIMESTAMP_FILTER
2019-12-13T06:07:10.189Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: peer_in WIRE_ACCEPT_CHANNEL
2019-12-13T06:07:10.744Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: signature 3044022041cee74c0fddc333787570674b6848c8e75b463bd44d34557153062c5526b13d02204ea643e68ce5274c3f61f26ae3ebe7779783b43148cfb738ff16969c2d396de101 on tx 0200000001d1051af7c4e2218cf21f1b450015148f134626cf4018fcc1580d898157dbc41501000000000e5f108001683f0f000000000016001456c9b57de7610ed4a7721cb5a7797e13ce53d9f47e5a5c20 using key 037ad0224ed47a6891ddc89fb5040f45305bdb8aa550a159fb8ad2fc36e0b8ab5f
2019-12-13T06:07:10.751Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: peer_out WIRE_FUNDING_CREATED
2019-12-13T06:07:10.952Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-openingd-chan#17314: peer_in WIRE_FUNDING_SIGNED
2019-12-13T06:07:11.557Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: pid 17024, msgfd 57
2019-12-13T06:07:11.562Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-chan#17314: Waiting for funding confirmations
2019-12-13T06:07:14.427Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: init LOCAL: remote_per_commit = 021b19f371e5874c270cf8d9d20be6da75c95d850de73d2dd496d89eb2028cc929, old_remote_per_commit = 021b19f371e5874c270cf8d9d20be6da75c95d850de73d2dd496d89eb2028cc929 next_idx_local = 1 next_idx_remote = 1 revocations_received = 0 feerates { SENT_ADD_ACK_REVOCATION:1006 } range 253-37670
2019-12-13T06:07:14.437Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: option_static_remotekey = 1
2019-12-13T06:11:22.709Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: peer_in WIRE_FUNDING_LOCKED
2019-12-13T06:11:22.727Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-chan#17314: Got funding_locked
2019-12-13T06:12:34.521Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-chan#17314: Got depth change 0->1 for 15c4db5781890d58c1fc1840cf2646138f141500451b1ff28c21e2c4f71a05d1
2019-12-13T06:12:34.543Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-chan#17314: Funding tx 15c4db5781890d58c1fc1840cf2646138f141500451b1ff28c21e2c4f71a05d1 depth 1 of 1
2019-12-13T06:12:34.694Z INFO 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-chan#17314: State changed from CHANNELD_AWAITING_LOCKIN to CHANNELD_NORMAL
2019-12-13T06:12:34.900Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: funding_locked: sending commit index 1: 023ff1bb81d3f0a1f2c476887d61e576aa327e622dba95f19c6099f87209ba60df
2019-12-13T06:12:34.932Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: peer_out WIRE_FUNDING_LOCKED
2019-12-13T06:12:35.016Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: We need 12727sat at feerate 3767 for 0 untrimmed htlcs: we have 1000000000msat/1000000000msat
2019-12-13T06:12:35.021Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Setting REMOTE feerate to 3767
2019-12-13T06:12:35.034Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: peer_out WIRE_UPDATE_FEE
2019-12-13T06:12:35.058Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Trying commit
2019-12-13T06:12:35.078Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Feerate: SENT_ADD_HTLC->SENT_ADD_COMMIT REMOTE now 3767
2019-12-13T06:12:35.851Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Creating commit_sig signature 1 304402205a882df21bac4672ce9be922b7956c154a48a12e901931f05c95b28ab04f5f7c02201a9caddffbce2a0e2e5fea5a49de541d2758e94a6e4f457a5e82f57ffcd1614201 for tx 0200000001d1051af7c4e2218cf21f1b450015148f134626cf4018fcc1580d898157dbc41501000000000e5f10800199370f000000000016001456c9b57de7610ed4a7721cb5a7797e13ce53d9f47f5a5c20 wscript 52210315803cac8097608a4ee5c0d863615fad5e118bc0618700680d6fe5cf9ecbe90421037ad0224ed47a6891ddc89fb5040f45305bdb8aa550a159fb8ad2fc36e0b8ab5f52ae key 037ad0224ed47a6891ddc89fb5040f45305bdb8aa550a159fb8ad2fc36e0b8ab5f
2019-12-13T06:12:35.867Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Telling master we're about to commit...
2019-12-13T06:12:36.133Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Sending master 1020
2019-12-13T06:12:36.341Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: ... , awaiting 1120
2019-12-13T06:12:36.760Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Nope, got 1027 instead
2019-12-13T06:12:36.792Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Got it!
2019-12-13T06:12:36.833Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Sending commit_sig with 0 htlc sigs
2019-12-13T06:12:36.863Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: peer_out WIRE_COMMITMENT_SIGNED
2019-12-13T06:12:36.896Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: Now dealing with deferred WIRE_CHANNEL_FEERATES
2019-12-13T06:12:36.995Z DEBUG 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-channeld-chan#17314: peer_in WIRE_ERROR
2019-12-13T06:12:37.052Z UNUSUAL 03634bda49c9c42afd876d8288802942c49e58fbec3844ff54b46143bfcb6cdfaf-chan#17314: Peer permanent failure in CHANNELD_NORMAL: channeld: received ERROR channel d1051af7c4e2218cf21f1b450015148f134626cf4018fcc1580d898157dbc414: rejected commitment: commit_height=1, invalid_commit_sig=304402205a882df21bac4672ce9be922b7956c154a48a12e901931f05c95b28ab04f5f7c02201a9caddffbce2a0e2e5fea5a49de541d2758e94a6e4f457a5e82f57ffcd16142, commit_tx=0200000001d1051af7c4e2218cf21f1b450015148f134626cf4018fcc1580d898157dbc41501000000000e5f108001683f0f000000000016001456c9b57de7610ed4a7721cb5a7797e13ce53d9f47f5a5c20, sig_hash=4cd3c264eac393d81b0426d713e98f9a89ba0f2253b1058660a06db9de381a4a