Awkwardly my Linux Biblepay client had banned node.biblepay.org for "misbehaving". That explains why my server had dropped out of the pool again an hour ago (pool.biblepay.org has the same IP). I've deleted the banlist.dat and hopefully it won't ban it again, but I think the same thing had happened one or twice over the past couple of days...
Let me know if the log shows a reason why it was misbehaving, if you happen to come across it.
I think it was an invalid share (from the pool?) Times below are in UTC:
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2017-09-12 10:06:57 DGW: Height 7268.000000, NewDiff 1b5d201e nActualTimespan 840.000000 nTargetTimespan 1680.000000 Before 0000000000ba403c666666666666666666666666666666666666666666666665, After 00000000005d201e333333333333333333333333333333333333333333333332 ^M
2017-09-12 10:11:19 89UpdateTip: new best=7c502466f0281830421fbc355eee96d7bcf7694fd0f469948769aecab03b55ac height=7269 log2_work=46.36036 tx=11141 date=2017-09-12 10:11:18 progress=1.000000 cache=0.0MiB(17tx)
2017-09-12 10:11:19 ProcessNewBlock : ACCEPTED
2017-09-12 10:11:41 DGW: Height 7269.000000, NewDiff 1b7983c0 nActualTimespan 1349.000000 nTargetTimespan 1680.000000 Before 0000000000975490999999999999999999999999999999999999999999999998, After 00000000007983c04d0369d0369d0369d0369d0369d0369d0369d0369d0369ce ^M
2017-09-12 10:12:18 89UpdateTip: new best=080e3fb48216963b171e057e4871430be6c33c3809988f9eb920ea7d774cde03 height=7270 log2_work=46.396887 tx=11142 date=2017-09-12 10:11:59 progress=0.999998 cache=0.0MiB(18tx)
2017-09-12 10:12:18 ProcessNewBlock : ACCEPTED
2017-09-12 10:12:24 CMasternodeSync::IsBlockchainSynced -- found enough peers on the same height as we are, done
2017-09-12 10:12:32 ERROR: CheckProofOfWork(): BibleHash does not meet POW level with TxIndex Lookup, prevheight 7270.000000 pindexPrev 080e3fb48216963b171e057e4871430be6c33c3809988f9eb920ea7d774cde03
2017-09-12 10:12:32 ERROR: CheckBlockHeader(): proof of work failed
2017-09-12 10:12:32 Misbehaving: 108.61.204.234:40000 (0 -> 50)
2017-09-12 10:12:32 ERROR: invalid header received 4807e741db78698ecdd8828c7ba1ae162a00ee0d8822657d399524ef7fa75d0e
2017-09-12 10:12:32 ProcessMessages(headers, 82 bytes) FAILED peer=1
2017-09-12 10:12:32 89ERROR: CheckProofOfWork(): BibleHash does not meet POW level, prevheight 7268.000000 pindexPrev 090c001c97cacca4166215be8a7cdb640273a068c104de4b51a704ae17b95175
2017-09-12 10:12:32 ReadBlockFromDisk: Errors in block header at CBlockDiskPos(nFile=0, nPos=3173046)UpdateTip: new best=4807e741db78698ecdd8828c7ba1ae162a00ee0d8822657d399524ef7fa75d0e height=7271 log2_work=46.434674 tx=11143 date=2017-09-12 10:12:29 progress=1.000000 cache=0.0MiB(19tx)
2017-09-12 10:12:32 ProcessNewBlock : ACCEPTED
2017-09-12 10:12:38 CMasternodeSync::IsBlockchainSynced -- found enough peers on the same height as we are, done
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2017-09-12 13:25:38 ProcessNewBlock : ACCEPTED
2017-09-12 13:25:38 ERROR: CheckProofOfWork(): BibleHash does not meet POW level, prevheight 7288.000000 pindexPrev 431b247c3cbd61e29f1edad55134f1c0c3e9689c3024752de5cc239c53071041
2017-09-12 13:25:38 ReadBlockFromDisk: Errors in block header at CBlockDiskPos(nFile=0, nPos=3181598)^M
** ProcessGetData:Cannot load block from disk.^M
2017-09-12 13:25:44 CMasternodeSync::IsBlockchainSynced -- found enough peers on the same height as we are, done
2017-09-12 13:26:53 89ERROR: CheckProofOfWork(): BibleHash does not meet POW level, prevheight 7289.000000 pindexPrev 8b59e22885de070cb91790c279e66f0a4ec3d0d19d2a9203729d8e984a341945
2017-09-12 13:26:53 ERROR: CheckBlockHeader(): proof of work failed
2017-09-12 13:26:53 ERROR: ProcessNewBlock: CheckBlock FAILED
2017-09-12 13:26:53 Misbehaving: 108.61.204.234:40000 (50 -> 100) BAN THRESHOLD EXCEEDED
2017-09-12 13:26:53 89UpdateTip: new best=709b269c65b9a67926110eba5e677a523e8c06910cd22716651705eb9c78cff7 height=7290 log2_work=46.90914 tx=11178 date=2017-09-12 13:26:49 progress=1.000000 cache=0.0MiB(64tx)
2017-09-12 13:26:53 ProcessNewBlock : ACCEPTED
2017-09-12 13:26:59 CMasternodeSync::IsBlockchainSynced -- found enough peers on the same height as we are, done
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