So as the headline literally states, Little Mix's next single will be 'Salute'. The announcement was 'teased' via an Instagram video, which posed the following question:
"Word on the grapevine is that Little Mix has a little announcement for you today. Could it be a new single from their album?"
The accompanying video then featured the 'girls' dancing to the song, so that's the answer to that really isn't it.
No news as to when it will be out but given that they start an arena tour next month, it will probably be around that sort of time.