Solution to 7A has been deliberately left unsolved and is to be answered only by a non-regular / novice commenter, with proper annotation. Those who have answered earlier in the week, please give others a chance.
Open for anyone to answer, if not solved by 1 PM.
ACROSS
6 Our closest living relative, Victor, takes me as subject for article (5) CHIMP CH(-a+i)IMP
7 Head off to exit beyond for journey (8) P?O?R?S? (Addendum - PROGRESS {eGRESS}<=>{PRO} - See comments)
10 Preview mobile home (7) TRAILER [DD]
11 Son, say, reportedly intended to separate (7) SEGMENT {S}{EG}{(~meant)MENT}
13 He leaves penthouse angry but determined (3,4) SET UPON PENThOUSe*
14 Convict consumed ecstasy, with judge as accomplice (11) CONFEDERATE {CON}{FED}{E}{RATE}
19 What a labour union might initiate - take up arms ? (4,3) WAGE WAR [DD]
21 Eastern representative involved in trial creates a violent uproar (7) TEMPEST {T{E}{MP}EST}
23 Nationalist hidden in shed after mother initially notices intensive search by police (7) MANHUNT {HU{N}T}<=>{MA}{No...s}
25 After retirement, mostly withdraw - bored by husband, right? (7) CHARTER {RETRACt<=} over {H}
26 A young bachelor drawn in by schemes for pleasure seekers (8) PLAYBOYS {PL{A}{Y}{B}OYS}
27 Birds seen in castles (5) ROOKS [DD]
DOWN
1 Huge mob circling around one model in Cannes at first (8) GIGANTIC {(+g)G{I}GAN(-g)}{T}{In}{Ca...s}
2 Say, people look frequently for God (6) APOLLO {sAy+PeOpLe+LoOk}
3 Pole left to testify in sweatpants possibly (10) SPORTSWEAR {S}{PORT}{SWEAR}
4 Difficulty going up heights... (4) TOPS <=
5 ...Unconscious? Doctor, please! (6) ASLEEP*
6 New Yacht club's popular (6) CATCHY {YACHT+C}*
8 Tense volunteers supporting royal after missing the last sailing event (7) REGATTA {T}{TA}<=>{REGAl}
9 Hurt? Essential to trust in God (5) STING [T]
13 Picks items abroad with distrust (10) SKEPTICISM*
15 Ruby somewhere in Berkshire ? (7) NEWBURY {RUBY}* [RA]
16 Boisterous celebration after missing another bar appointment (8) ELECTION CELEbraTION*
17 Later, quietly moved through water in flood (5) SWAMP {P}<=>{SWAM}
18 Reserves plots after disposing of investments at first (6) STORES STORiES
20 Urgent letter about tender (6) GENTLE [T]
22 Poor Mike - earnest, we hear (6) MEAGRE {M}{(~eager)EAGRE}
24 Primarily, tired runners often try to move at a steady pace (4) TROT Acrostic
Reference List
Son = S, Ecstasy = E, What = W, Eastern = e, Representative = MP, Nationalist = N, Husband = H, Young = y, Bachelor = B, Model = T, Pole = S, Club = C, Tense = T, Volunteers = TA(Territorial Army), Quietly = P, Mike = M