This makes me feel better about being charged £400 more than I expected lol .. I went ahead with the booking after receiving the advice above from Karfa...

Though strangely I just checked my credit card and the only pending charge is one for £60 .. which is what I had expected to pay to begin with ... HmMMMM...... And I have my new confirmation but no indication as to what was actually charged. I just hope the world is somewhat back to normal and these flights can go ahead in late April because I can only imagine how tangled this may get if I have to change the flight....