Some inventory seems to be back up. Just booked a one way to LHR on United from EWR for 20,000 miles. LM is still charging a mystery tax of approximately 25$ (in addition to the normal booking fee) but it's still good value compared to the 30,000 miles United wants for this itinerary. Nonetheless, I have now spent down my balance of LM miles and assuming this flight sticks, I am done with this program and its highs and lows.