The first of Azed’s Letters Latent puzzles since VE(S)TAL in 2009. I won’t give the complete preamble since you have no doubt already seen it, but letters are missing from each answer whenever they occur and these missing letters make an appropriate seasonal quotation. The definition is to the whole word, the subsidiary indication to the word with letters missing. Two words are missing from this quotation and the first one is clued like all the rest in the puzzle; the second one is the competition clue-word.
In the answers I have given the omitted letters in lower-case.
The quotation (which I have to admit to finding using Google) was from Ernest Dowson: ‘pale amber sunlight falls across the [reddening October] trees’.
As with all Azed’s specials, this was much enjoyed.

Across
1 Sweet name I’m given in pedigree, traced back (10)
pEppERMINT
6 Fluid germicide? It symbolizes the working man (7, 2 words)
FLaT CaP
11 Tide in conflict with Canute scored? (11)
DENTICUlATE
(Tide Canute)* — I don’t quite see the link between denticulate, which is an architectural term indicating the presence of tooth-like elements, and scored, which seems to be about scratching
12 Soft drinks I mark being imbibed by boys (8)
LIMeADeS
13 Pulpit: it provides demure Scots with odd extracts from bard (6)
MIMBaR
14 Varied rep is including Queen Elizabeth with English leading ladies (9)
PREmIERES
17 Method for assembling data organized to rules (10, 2 words)
bUbbLE SORT
18 One selling dog in expensive car? (8)
ReTAILeR
R(tail)R — the Rolls-Royce is the expensive car
21 Matter brought before eastern paymaster formerly (6)
PUrSEr
23 Green ecofreaks will include this ancient ascetic (6)
EssENE
Hidden in GrEEN Ecofreaks
24 New doctor, beard pulled back (7)
uNDRAWN
25 US censorious, say, on return of musical (8)
nEGATIVE
eg (Evita)rev. — in the US this means censorious — this clue is printed in bold in the paper, but the boldness doesn’t appear online, which seems to confirm my suspicion that it was meaningless
29 Tropical fever: remedy includes what’s drunk neat (9)
CAlENTURE
31 Traditional Islamic text experienced on Thursday (6)
HADiTH
32 Swirling eddies? Get clear of rim (7)
DISEDgE
(eddies)* — but according to Chambers this Shakespearean etc word means to deprive of the edge in the sense blunt, not to move away from the edge
33 Algae pilot’s to steer uneasily round (11)
hETEROCONTS
34 Old royal on the outside, right at the back (6)
REtRAL
re(r)al — real as in real tennis, royal tennis
35 Philosophical discipline somehow hinges round what’s central to Confucius (8, 2 words)
fENG SHUI
{Conf}u{cius} in (hinges)*
Down
1 Protective appendage careless player always discarded (6)
EaRLaP
2 Form of compulsory marriage on the up I have to reprove (8)
lEVIRATE
3 Part of cereal plant, Middle East one that is (6)
MEAlIE
4 Inadequate as a serious volume, oddly lined, executive penned (9)
INDEXLEss
5 Pacific tree fruit, for which repayment date is fixed (8, 2 words)
TIME LOaN
7 Old Roman I, not active in Hawaian parties (6)
LUcIUS
I not a in luaus — surely it’s Hawaiian unless there is something devious going on that I haven’t noticed
8 Pulpit university installed, perched up, they drone musically (9)
TAMBOUrAS
(ambo U) in (sat)rev. — two references to a pulpit in clues that cross
9 See preamble (7)
oCToBER
This is the second of the words missing from the quotation, the clue-setting competition word
10 Shut up, having to accept ceremonial constantly repeated (10)
PERsIsTENT
15 One uttering shrill cry (animal by the sound of it?) (9)
sCREECHER
16 Spanish port, more reasonable by implication? (9)
SANtANDER
‘San’ and ‘er’ make ‘saner’, or more reasonable
19 Plan to recover lost territory (English version, given in bar) (8)
REVANChE
20 Divine centre of almandine in fiance’s gift – what’s bride, typically? (9)
ReDDeNING
22 Duelling scar duke revealed amid rising boasts, for all to see (8)
SWORDCUt
26 Major, leader of expedition in attendance (7)
GrEATEr
27 Wiliness shown up around court and so on (8)
eTCeTeRA
28 Loathes delirium surrounding holy man (7)
DeTeSTS
30 I shelter climbing umbellifer (6)
sEsELI
Thanks John, as always it took a bit of time to get started but it was very enjoyable. After finishing I spent a while wondering quite how Azed can possibly produce these puzzles, the phrase ‘tour de force’ gets used rather too often on this site in my opinion but it really could be used properly here. Simply assembling a grid of Letters Latent answers would be beyound me, to do it with them forming a quotation is remarkable.
Anyway, Chambers definition (in my edition) only gives the ‘with dentils’ definition (more usually ‘denticular’ or ‘with dentils’ when I made such architectural features) but the OED has Having small teeth or tooth-like projections; finely toothed which is pretty close.
Shame we’ll probably have to wait a good while for another one.
I agree with sidey that this is a tour de force, and it also took me a long time to get started. Once the quotation became clear, (and I too had to google it) finishing the puzzle became much easier. My Chambers gives “notched” as a definition for “denticulate”, which isn’t so far from “scored”. I agree about DISEDGE.
Perhaps worth mentioning that LUCIUS and SANTANDER were the two words not to be found in Chambers, although the latter name will certainly be familiar to solvers in the UK (and in Spain, of course).