Leaving UK whilst awaiting a decision

Hello all,

My wife has applied to ILR and whilst awaiting a decision the Spousal visa has expired (we did everything in time, it's just taken months for a decision to be made).

As her visa ran out in May (honestly we did all the applications before this) she is now without a visa.

Her grandma is now very sick and could be about to pass away soon. If she leaves the UK for an emergency visit/funeral, will she be able to get back to the UK? Is there any emergency visa permission we can use for this?