I like making these way too much...
I'd like to make a list of every LT route
in the order of conversion Here's my list, based on actual operations rather than official dates. Note that the end month for a phased conversion is when the route in theory had enough LTs to operate the full service, in practice several routes continued with one or two other buses each day for some time afterwards. Neither is it the month the last LT allocated to that route entered service.
"38X" - First LT 27/02/2012, services gradually increased 04 - 08/2012 as more prototypes entered service (initial services on route 38, but not part of normal timetable)
38 - First LT 15/06/2013 (prototypes running part of normal 38 service, replacing 38X)
24 - Full conversion 22/06/2013
11 - First LT 20/09/2013, phased conversion 09 - 10/2013
9 - First LT 24/10/2013, full conversion 26/10/2013
390 - First LT 05/12/2013, full conversion 07/12/2013
148 - First LT 05/02/2014, full conversion 15/02/2014
38/N38 - Phased conversion 04 - 06/2014 (N38 first LT 15/05/2014, phased conversion 05 - 06/2014)
8/N8 - First LT 19/06/2014 (N8 27/06/2014), phased conversion 06 - 07/2014
453 - First LT 18/10/2014, phased conversion 10 - 11/2014
137 - First LT 02/12/2014, phased conversion 12/2014
55/N55 - First LT 17/01/2015 (N55 31/01/2015), phased conversion 01 - 02/2015
15 - First LT 02/03/2015, phased conversion 03/2015
12 - First LT 28/03/2015, phased conversion 03 - 05/2015
73/N73 - First LT 14/05/2015 (N73 15/05/2015), phased conversion 05 - 07/2015
88 - First LT 22/08/2015, phased conversion 08 - 09/2015
16 - First LT 25/09/2015, phased conversion 09 - 10/2015
N11 - First LT 11/10/2015, phased conversion 10/2015 (at least that's what my spreadsheet says, I seem to remember it actually took longer to fully convert)
149 - First LT 13/10/2015, phased conversion 10 - 12/2015
168 - First LT 10/12/2015, phased conversion 12/2015 - 01/2016
159 - Full conversion 12/12/2015
68 - First LT 06/02/2016, phased conversion 02 - 04/2016
3/N3 - First LT 09/02/2016, phased conversion 02/2016
211 - First LT 18/03/2016 (occasional operation at this stage using spare buses from 3 and 159)
59 - First LT 22/03/2016, phased conversion 03 - 04/2016
91 - First LT 09/05/2016, phased conversion 05 - 06/2016
211 - Phased conversion 05 - 06/2016
189 - First LT 30/06/2016, phased conversion 09/2016
253/N253 - First LT 01/09/2016 (N253 20/10/2016), phased conversion 10 - 11/2016
21/N21 - First LT 05/12/2016 (N21 07/12/2016), phased conversion 12/2016 - 01/2017 (N21 not fully operated by LTs at this point, even on NX duties, due to BX part allocation)
EL3 - New route with full LT operation from 18/02/2017
48 - First LT 25/02/2017 (only partial conversion at this stage using LT234-8)
EL2 - First LT 02/03/2017, phased conversion 03 - 04/2017
EL1 - First LT 08/03/2017, phased conversion 03 - 06/2017
76 - Full conversion 25/03/2017
N21 - Full conversion 28/05/2017
48 - Phased conversion 06 - 08/2017
254 - First LT 17/06/2017, phased conversion 06 - 08/2017
32 - First LT 07/08/2017 (occasional operation only, using spare buses from 16 and 189)
N15 - Full conversion 26/08/2017
5 - First LT 26/08/2017 (normally early / late services crosslinked with N15 only)
267 - First LT 07/11/2017, phased conversion 12/2017 - 01/2018
Regarding crew operation, 38X/38 before full conversion usually was crew operated though I believe OPO might have been trialled at some point. Routes 24 and 11 initially had CAs 7 days a week however the 24 seems to have gone to Monday - Friday when the 390 converted with the same times of crew operation. The 9 and 10 also ran with CAs on weekdays only, as did the 38 after conversion but not beyond Mildmay Park. So the 148 was indeed the first OPO route to fully convert, while the next route (38) was the last with CAs.