A thoughtfully constructed Quiptic from Chandler to ease us into Greenwich Mean Time.
Abbreviations
cd cryptic definition
dd double definition
cad clue as definition
(xxxx)* anagram
anagrind = anagram indicator
[x] letter(s) removed
definitions are underlined
Across
1 With time gone, terrible deficit facing European building
EDIFICE
A charade of (DEFICI[T])* and E. The anagrind is ‘terrible’ and ‘with time gone’ tells you to remove the T.
5 Expression of surprise about posh US city offering rich stew
GOULASH
An insertion of U and LA in GOSH. The insertion indicator is ‘about’. U (as opposed to non-U) for ‘posh’ is just crosswordspeak. Nobody ever uses it these days in any serious conversation.
10 Glowing ring with a loft in part
HALO
Hidden in witH A LOft.
11 Muddle with greens in a poor state for couriers
MESSENGERS
A charade of MESS and (GREENS)* with ‘in a poor state’ as the anagrind.
12 Entertainment in a field cancelling opening? It’s not reasonable
UNFAIR
[F]UNFAIR
13 Start to eye opening in good equestrian activity
EVENTING
A charade of E, VENT, IN and G.
14 Increase the risks in haunt Pete constructed
UP THE ANTE
(HAUNT PETE)* with ‘constructed’ as the anagrind.
16 Chaps in audience making appearance
GUISE
A soundalike clue (‘in audience’) for GUYS.
17 Fellow is given direction in banquet
FEAST
A charade of F and EAST.
19 Eccentric sent a bike to get mixed drink
SNAKEBITE
(SENT A BIKE)* with ‘eccentric’ as the anagrind. A mixture of half a pint each of cider and lager. Very 1980s. The internet describes it as a ‘cocktail’. I don’t think so.
23 Inspector has to emphasise extreme sorrow
DISTRESS
A charade of DI and STRESS.
24 Observe warning
NOTICE
A dd.
26 One giving advice is elected local politician, reportedly
COUNSELLOR
A soundalike clue (‘reportedly’) for COUNCILLOR.
27 Dry element in bar identified
ARID
Hidden in bAR IDentified.
28 Figure still in filthy site
SEVENTY
An insertion of EVEN in STY. The insertion indicator is ‘in’.
29 Took up commercial work with Edward shortly
ADOPTED
A charade of AD, OP and TED.
Down
2 Attraction with play on words in turn formulated
DRAWN UP
A charade of DRAW and PUN reversed.
3 A number provided in promotion for female
FIONA
A reversal of A, NO and IF. ‘In promotion’ works as a reversal indicator because it’s a down clue.
4 Cold region in Italy, area with many lakes
CUMBRIA
A charade of C and UMBRIA.
6 Item in kitchen drawer in first section?
OPENER
A dd.
7 Delicate bachelor starts to use little burner – it glows?
LIGHT BULB
A charade of LIGHT, B and ULB for the initial letters of ‘use’, ‘little’ and ‘burner’.
8 Section of an orchestra as could be pulled?
STRINGS
A dd.
9 Act confidently in fearless tones possibly
ASSERT ONESELF
(FEARLESS TONES)* with ‘possibly’ as the anagrind.
15 Ambassador with view about India showing indecision
HESITANCE
A charade of HE for His Excellency or ‘Ambassador’ and I inserted into STANCE. The insertion indicator is ‘about’.
18 Medical incident in part of a series
EPISODE
A dd.
20 Sort wine of a similar sort
KINDRED
A charade of KIND and RED.
21 Performer wearing hat that is pleasant to touch
TACTILE
An insertion of ACT in TILE. The insertion indicator is ‘wearing’.
22 Modern headquarters having an exchange of parts
RECENT
Chandler is inviting you to swap parts of CENT RE.
25 Vagrant close to last entry to a car park
TRAMP
A charade of T for the final letter of ‘last’ and RAMP.
Many thanks to Chandler for this week’s Quiptic.

Perfect quiptic. Thanks both. GUISE was last in. Not common for I to follow U. (Held up by Guinivere recently.)
I was unsure how to parse 22d, wrongly assuming it was an anagram of centre = headquarters. I wonder if this clue is a bit difficult for beginners?
New for me: snakebite = mixed drink.