Age of the World

This is a scratch space for an approximation, but... I've decided that this setting is 1,227 years old, as of Denziu's story with the Tachanigh-Kelkaith (my first manuscript). Other stories will need to know their offset from that one.
I've decided that Theoma started in the springtime, and measures its years from the start of spring planting.
Denziu's story takes place in the summer of 1,227.
Aleicree's story (my second manuscript) takes place the autumn after Denziu's story, and so as of Aleicree's story Theoma is still 1,227 years old.
Ekis' story (my third manuscript) also takes place the autumn after Denziu's story, and so as of Ekis' story Theoma is still 1,227 years old.
Taltios' story (my fourth manuscript) takes place the next summer after Denziu's story, so as of Taltios' story Theoma is 1,228 years old.