Across:
1 In a corner (trapped) without parking (p) ('trapped' without 'p' = traped)? Reverse (= reverse indicator) (traped = DEPART) and go someone else! (DEPART),
4 All that’s left of the opposition when they’ve been mauled by The Lions (CARCASES)? The decaying bodies of the Springbok! (decaying bodies of the springbok/gazelle = CARCASES),
9 Small (S-) spot on the bottom (‘spoT’ on the bottom = -T-) of the foot (-ARCH) (STARCH) creates a type of stiffness (STARCH),
10 Red tops do this to sensationalise (‘red tops’/tabloids SPLATTER news) Beano’s depiction of death perhaps? (cartoon ink ‘SPLATTER’ perhaps),
12 The Apprentice (intern) is not finished (n) (‘intern’ without ‘n’ = INTER-) getting both sides to feature (getting both sides to ‘FEatuRE’ = -FERE) (INTERFERE) or get involved in someone else’s business (INTERFERE),
13 A flap (LAPEL) in large (L-) gym (-PE-) in Alabama (AL = -A-L) (LAPEL),
14 Contests (COMPETITIONS) firm (CO-) is getting 1000 (-M-) formal requests with signatures (-PETITIONS) (COMPETITIONS),
18 Still (NEVERTHELESS) no chance (NEVER-) finding most of (m) them (them) (‘them’ without ‘m’ = THE) from Takeaway (take away = -LESS) (NEVERTHELESS),
21 Squash (gourd) without head of radicchio (head of ‘Radicchio’ = r) (‘gourd’ without ‘r’ = GOUD-) and a (-A) (GOUDA) type of cheese (GOUDA),
22 Sorry about this (APOLOGISE), as it’s a (A-) bit of horseplay (-POLO-) for soldiers (GIs = -GIS-) from Spain (-E) (APOLOGISE),
24 One (I) speech (= homophone indicator) (‘I’ = ‘eye’ = EYE-) at faculty (-SIGHT) (EYESIGHT) provides vision (EYESIGHT),
25 What one exercising strong-arm tactics produces perhaps (BICEPS) in seafood (mussels) report (= homophone indicator) (‘mussels’ = ‘muscles’ = BICEPS),
26 It’s still (serene = SEREN-E) about Bill (-AD-) (SERENADE) – the romantic type heard under the balcony (SERENADE),
27 Gael leaving Los Angeles (‘Gael’ leaving ‘Los Angeles’ = losnes = LESSON) will learn from this (LESSON).
Down:
1 It's as plain as day (DISTINCT) for detective (DI-) upsetting (= reverse indicator) local foolish types (nits = STIN-) going to court (-CT) (DISTINCT),
2 A diversion for the little ones after school (PLAYTIME) period in the abbey? (period in The Abbey Theatre = play time = PLAYTIME),
3 Part of the unfolding (= reverse indicator) picture card (part of the unfolding ‘pictuRE CARd’ = recar = RACER) of one looking for speed (RACER),
5 Thanks for the review (APPRECIATION) of new (= anagram indicator) Croatian pipe (Croatian pipe = APPRECIATION),
6 Conversion (CHA-NGE) goes over loose-head (‘Loose’ head = -L-) at the French (‘the’ French = -LE-) (CHALLENGE) Test (CHALLENGE),
7 Ace gets out of spacesuit (‘ace’ gets out of/ from ‘spacesuit’ = spsuit = SIT-UPS) for a number of exercises (SIT-UPS),
8 Small (S-) type of bridge (-T-OLL bridge) over river (-R-) (STROLL) is perfect for those going a short distance (STROLL),
11 Half of seminary (half of ‘SEMInary’ = SEMI-) is cut-off (-DETACHED) (SEMI-DETACHED) from those sharing with the neighbours (SEMI-DETACHED),
15 Train (= anagram indicator) – leave on it (leave on it = ELEVATION) to higher ground (ELEVATION),
16 Does a job (DELIVERS) designing (= anagram indicator) red veils (red veils = DELIVERS),
17 Welcomes (USHERS IN) those putting them in their place (USHERS) up (= reversal indicator) north (NI = IN) (USHERS IN),
19 Serge’s (serges) complex (= anagram indicator) (serges = EGRESS) is way out (EGRESS),
20 Stylish director (AUTEUR) loses head (h) with overbearing arrogance (‘hauteur’ without ‘h’ = AUTEUR),
23 Fair amount of (half) The Stones (stones/seeds = pips) (half of ‘PIps’ = -PI-) taken in by individual (one = O-NE) (= OPINE) with sound off (sound off = OPINE).