Update today from the BBC:
The pad was originally scheduled to open in 2019. The latest issue is one of window strength in the top 2 floors of the tower - that the fixings may not be strong enough to cope with rotor downwash. Tests should be completed by the end of the year.........................
Watch this space, but do not become over-excited.
How did we get this far without a basic understanding of what's needed? Wish I knew.