Originally Posted by Cheetah_SA

I checked on the app this morning and all D/G and E/F seats were blocked as were some side seats too. Expertflyer confirmed that the centre seats were indeed blocked and not taken. A few minutes ago I checked on the web site and all the previously blocked seats were suddenly available! So I moved us to an E/F pair. Just to be sure I checked that my choices have stuck. They have - but now the blocking is back again!

Bizarre.