Thanks for the reply.
Since I am arriving at 0530, it is highly unlikely that there will be anybody at the transfer desk

I see that the lounges are open 24 hours and will try to see if LH will let me into their SEN lounge in SU lounge refuse to let me in for more than 2 hours(even though I am flying SkyTeam, not Star)- I have about 4 hours 30 min to kill in the early morning.