Fix for broken incoming data

Incoming data borked in a new way: misordered timestamps, now repairable (by discarding anything older than the newest seen so far) so as to not lose a day (though still worrying)...

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WARNING: [FUELINST, 20230122, 12, 20230122055500, 5380, 0, 501, 5171, 6616, 0, 374, 0, 190, 651, 400, 1002, 153, 2017, 989, 259, 384, 1257]
WARNING: [FUELINST, 20230122, 12, 20230122060000, 5779, 0, 500, 5172, 6614, 0, 374, 0, 165, 547, 400, 1003, 127, 2005, 985, 251, 344, 1257]
WARNING: [FUELINST, 20230122, 13, 20230122061500, 6749, 0, 498, 5175, 6601, 0, 377, 0, 166, 125, 400, 1003, 51, 2010, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 13, 20230122062000, 6951, 0, 500, 5175, 6539, 0, 376, 0, 167, 125, 400, 1003, 45, 2014, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 13, 20230122060500, 6320, 0, 499, 5177, 6617, 0, 375, 0, 164, 249, 400, 1003, 102, 2001, 867, 236, 260, 1257]
WARNING: [FUELINST, 20230122, 13, 20230122061000, 6575, 0, 499, 5175, 6656, 0, 377, 0, 165, 125, 400, 1004, 77, 2010, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 13, 20230122062500, 7171, 0, 499, 5176, 6489, 0, 375, 0, 168, 125, 397, 1004, 68, 2013, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 13, 20230122063000, 7055, 0, 500, 5179, 6458, 0, 374, 0, 187, 125, 376, 1004, 93, 2016, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 14, 20230122063500, 7265, 0, 501, 5172, 6454, 0, 374, 0, 181, 125, 352, 1002, 119, 2015, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 14, 20230122064000, 7410, 0, 499, 5167, 6454, 0, 375, 0, 195, 125, 326, 1003, 144, 2016, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 14, 20230122065500, 8015, 0, 499, 5175, 6585, 0, 379, 0, 168, 125, 251, 1001, 129, 1996, 863, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 14, 20230122064500, 7511, 0, 499, 5169, 6470, 0, 375, 0, 205, 125, 302, 1003, 168, 2016, 862, 227, 219, 1257]
WARNING: [FUELINST, 20230122, 14, 20230122065000, 7752, 0, 499, 5171, 6512, 0, 375, 0, 170, 125, 276, 1003, 154, 2009, 863, 227, 219, 1257]
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