There seems to be 2 x red exp. vessels and 1 x white, one red is adjacent to the boiler?, what volume is this.
You can tell easily if the installed exp. volume is sufficient by turning on all heating systems and noting the boiler pressure when all systems hot, if not > 2.5bar then OK from a expansion point of view but maybe other reasons for installing extra one?.
Can you also post a close up photo of the UPM pump, when its running, don't know if its running on one of its manual modes or is PWM controlled.