Thank you , Bernard, for the reference to the jet Bo Beep / pattern 1263 in Cottle (page 66, by the way, for other interested parties).
As to evidence for less-than-strict non-chronological dating of some Sowerby pattern numbers…
for the past year or so, for my own ‘entertainment’ I have been building a database correlating Sowerby RD numbers with their pattern book numbers, cross referencing them to the appropriate pattern book pages and, wherever possible, photos of each pattern in as many variants of size and colour as possible – a bit like Cottle crossed with Slack, Thompson, Murray, Lattimore etc. (but with knobs on and lots more pretty pictures). It has been an interesting exercise which has filled in lots of gaps (and time), though still far from complete (especially the flint glass tableware ranges).
Here are a few short sequences from my database showing RD numbers, followed by corresponding registration dates, Sowerby pattern numbers, and pattern book pages showing the pattern number. The chronological anomalies should be self evident.
260802 29 February 1872 – P5 1035 XI, p57
267742 7 November 1872 – P7 L1402 XI, p47
274743 31 July 1873 – P5 1054 XI p19
282663-664 1 June 1874 – P8 1080 XI, p2
282663-664 1 June 1874 – P8 1671 IX, p12
288210 1 January 1875 – P2 1088 XI, p14
282663-664 1 June 1874 – P8 1080 XI, p2
282663-664 1 June 1874 – P8 1671 IX, p12
288210 1 January 1875 – P2 1088 XI, p14
317234 17 December 1877 1280 IX, p5
318789-795 20 February 1878- P3 1397 XI, p59
318789-795 20 February 1878 - P3 1315 IX, p6
318792 20 February 1878 – P3 1291 IX, p5
319585 20 March 1878 – P7 1298 IX, p5
319589 20 March 1878 – P7 1299 IX, p6
323400 8 July 1878 – P9 1325 IX, p6
323400 8 July 1878 – P9 1325½ IX, p6
323400 8 July 1878 – P9 1400 IX, p8
325097 16 August 1878 – P11 1329 IX, p6
333424-429 17 March 1879 1403½ IX, p8
333427 17 March 1879 1392 IX, p7
334637 28 April 1879 1408 IX, p8
334642 28 April 1879 1423 IX, p8
335972 6 June 1879 1411 IX, p8
336595 30 June 1879 1422 IX, p8