HMS Queen Elizabeth was never the flagship of the 5BS.
From its inception in Oct 1915 and until the final day of the war HMS Barham was the only flagship of the fast squadron.
The 5BS was also the only Grand fleet squadron which comprised solely ships of the one class, the supreme Queen Elizabeths.
When first commissioned the QE was a nominal member of the 4BS, but went straight to the Med. On her return in May '16 she joined the 5BS but went straight into dockyard hands at Rosyth, subsequently missing the big contretemps on the 31st and June 1st.
On completion of her dockyard work, she rejoined the 5BS with her 4 sisters and in Feb 1917 left to become the fleet flagship,Beatty, as such she was unallocated.
A full broadside. The traditional English salute.