According to the recent Onboard Updates, effective July 1, language positions will be suspended on all flights to and from LHR.
Onboard Service indicates that the July schedule's language positions for the LHR trips will be replaced with non-language positions. The non-language flying will be assigned to the same domicile as the original language positions.
Because LQ flight attendants are no longer obligated to fly a language line, these language-qualified flight attendants might gain additional schedule choices---but whether or not that's advantageous in the real world depends on the domicile seniority, of course.
What about other segments? At this time, Onboard Updates says that "there are no plans to suspend language-qualified positions in other markets."
Pursers can remember this: you still have the authority to approve language incentive pay (LIP) for language qualified flight attendants. As always, this must be done "as provided for, and under the circumstances outlined in the Inflight Handbook on Page 1722."