Across:
8 Is getting out of Carlisle (‘is’ getting out of ‘Carlisle’ = carlle = CELLAR) for a basement in Bordeaux (CELLAR),
9 Drives away (REPULSED) with skinhead (‘Skin’ head = -S-) in new (= anagram indicator) Prelude (prelude = REPUL-ED) (REPULSED),
10 Limits to radiographic survey (limits to ‘RAdiographic survEY’ = raey) going all the way back (= reverse indicator) (raey = YEAR) 12 months (YEAR),
11 Spartan (GREEK) handy gear (gloves/mitts) reportedly (= homophone indicator) (‘mitts’ = ‘myths’ = MYTHS) (GREEK MYTHS) studied by past masters who know a lot about Amazon and the Midas touch (GREEK MYTHS tell you a lot about legendary Amazon and the Midas touch in Greek mythology),
12 No Lent in East Berlin (no ‘lent’ in ‘East Berlin’ = easbri = SERBIA) or in Central Europe (SERBIA),
14 Ulster (U-) Protestant leader (‘Protestant’ leader = -P-) is going steady (-DATING) (UPDATING) and that’s refreshing (UPDATING),
15 The odds on Hamlet’s dead father getting back his crown (A GHOST OF A CHANCE) – bet that’s a slim possibility (A GHOST OF A CHANCE),
18 Chewed over (PONDERED) the small lake (pond = PON-D) containing the foreign (‘the’ German = -DER-) weeds at the centre (‘weEds’ at the centre = -E-) (PONDERED),
20 Plagiarises from (STEALS) Ibsen out of beastliness (‘Ibsen’ out of ‘beastliness’ = atless = STEALS),
22 Tricky (= anagram indicator) casino game (casino game = EGOMANIACS) for those excessively conceited (EGOMANIACS),
24 Plays the lead, for instance (ACTS), in Cast- (cast) -away? (= anagram indicator) (cast = ACTS),
25 Union (MARRIAGE) flips, over (= reverse indicator) for example (e.g. = -GE), atmosphere (air = -RIA-) linked to strike (ram = MAR-) (MARRIAGE),
26 Outstanding (UNPAID) type of work one associates with interns (UNPAID work).
Down:
1 Break a promise (RENEGE) to Rocky (= anagram indicator) Greene (Greene = RENEGE),
2 Obscure (BLUR), miserable (blue) endless (e) (‘blue’ without ‘e’ = BLU-) writing (from the 3Rs = -R) (BLUR),
3 One can boast (BRAGGART) badly behaved child (BRA-T) caught one thousand (G-) fish (-GAR-) (BRAGGART),
4 Gets caught up (= reverse indicator) in sheer frustration (gets caught up in ‘shEER Frustration’ = eerf = FREE) of looking for work with nothing on (FREE),
5 Added some alcohol (SPIKED) to small (S-) fish (-PIKE-) dish, for starter (‘Dish’ for starter = -D) (SPIKED),
6 Put down (-LAY) in deep hole (pit = P- IT) that’s not dangerous (SAFE) (PLAY IT SAFE) to avoid taking risks (PLAY IT SAFE),
7 Chance I’m (chance I’m) off (= anagram indicator) (chance I’m = MECHANIC) operating on jaguars that aren’t running properly (MECHANIC),
13 The old Queen (Mary I of England = BLOODY MARY) presumably served in The King’s Arms? (The King’s Arms pub) (BLOODY MARY),
14 Not catered for (UNFED) in Hungary (Hungary), in a manner of speaking (= homophone indicator) (‘Hungary’ = ‘hungry’ = UNFED),
16 Unstable (= anagram indicator), ageing or (ageing or = GEORGIAN) English architecture (GEORGIAN),
17 Group of actors (CAST-) and the lead from Sive (the lead from ‘Sive’ = -S), not in (out = OUT) (CASTS OUT) Exiles (CASTS OUT),
19 A launch pad for the Sky (RUNWAY) series (RUN-) at a venue? (‘a venue’ = ‘avenue’ = -WAY) (RUNWAY),
21 Don’t adhere to restrictions locally (LET RIP) for the French (‘the’ French = LE-) holiday (trip = -T RIP) (LET RIP),
23 The zone (AREA) on both sides of Arabian Sea (on both sides of ‘ARabian sEA ‘ = AREA),
24 Snakes (ASPS) and newts removed from wasp’s nest (‘newts’ removed from ‘wasp’s nest’ = asps = ASPS).