“Ten answers have been affected by an IT FEATURE and must be amended before entry in one of two ways. For the remaining clues, half contain a superfluous word which must be relocated into one of the clues in the other half before solving. Numbers in brackets refer to entry lengths. Letters in the four shaded cells can be arranged to provide an acronym of the IT FEATURE, which must be written in full below the grid. Chambers Dictionary (2016) is recommended; two answers are abbreviations.”
Everyman 3,848
The puzzle may be found at https://www.theguardian.com/crosswords/everyman/3848. As usual for Everyman, there is the ‘primarily’ clue at 27A, and the rhyming pair …