Although the war was going very unfavorably for him, Tsar Ferdinand of Bulgaria did receive some good news — that among the Four Great Powers of the Allies, two of them belonged to the Saxe-Coburg-Gotha Family, like himself.
Although neither King George V of Britain nor King Arthur of Australasia were closely related to Ferdinand, they were still his kinsmen from the same family, so there should have been no need for complete extermination.
With such expectations, Ferdinand began attempting to contact the Allies, discussing how to end the war with smaller losses.
Yes, although a large number of Bulgarian troops were still fighting bravely on the front lines to defend their country, Ferdinand, who was in Sofia at that time, was already thinking about how to protect his own and the royal family's interests and how to stabilize his position after the war.
