Cedric expected this result. The moment the Church suspected him of being a summoner, he realized someone must have betrayed him. Furthermore, it had to be someone inside the royal palace.
Therefore, it was expected that whoever wanted Cedric dead would be alerted upon his return to Aeloria. Cedric had no way of preventing that unless he forged a new identity as an adventurer and took a quest inside Aeloria. That would require months of work.
Aria also seemed to notice the same thing. The petite professor was a recognized clairvoyant who had inherited the memories of a dragon. The two shared a glance and understood that their peaceful trip had ended.
"Our arrival has been reported," Cedric told Ember once they were out of the gates. Ember looked at him with confusion and then at Aria, who nodded in agreement. "We need to escape the forest as soon as possible."