My wife is Mexican whilst I am British. We recently married and she has a Spousal/Partner Visa (Leave to Remain)

I presumed that when returning from a holiday to Mexico, my wife would have to queue separately from me because she is from outside the EU, but upon talking to a work colleague, I'm told this may not be the case.

Does anyone know if my wife can join the same queue as me when we return to London Heathrow?