It's been a long time coming, but we've got to the kick off, and Matador is up and running!
However, I feel that everything depends on how good a sortee Force Z manages. If the catch some of the Japanese transports at sea (even if the Force is later mauled / destroyed by Japanese air power) then the thr invasion will be severly delayed, even completely scuppered.
Best case scenario for the British (bit not this most excellent TL) is Phillips rolls lots of 6's defeats the covering group and sinks all the transports. Invasion? What invasion! Although Gort would have some explaining to do about invading a Nuetral power unnecessary. The RN would be like, sinking ships? It's what we do 😉! Although I don't think Coxy would be so cruel to spend 2+ years serting the scene to finish the TL in an afternoon of naval armagedon!
Much more likely is that Force Z either engages or chases away some of the transports (helping the cause on land a great deal) foe the cost of having some ships damaged or destroyed either by the covering group or long range land based air power.