Building routines for pre-school aged students is all about preparation.
You want to ensure that your young child knows the plan, knows the expectations, and has ample time to ask clarifying questions (even if those questions are just variations on "why?")
Before a change to routine, I typically recommend giving your preschooler at least 3-4 weeks to start practicing for the change, especially if you find your child to tend toward anxious reactions.
Practice the skill before you need it.
Rather than requiring your preschooler to adapt to a new routine on the first day, build in lots of time to go through that new routine together - when you are able to take longer to process, answer questions, and you don't have a time restraint of your own adding pressure to the situation.
Earlier this year I was quote in a Romper article on setting up schedules at the beginning of the school year. As mentioned above, I recommend practicing the skill early and giving yourself ample opportunity to explain why changes are happening - but you should also make sure that you maintain a calm, patient attitude even in the face of your child becoming uncomfortable with what may seem like a small change to you.
When to seek a second opinion:
If you've gone a few weeks with a change to routine that is still causing troubles for your child, or if their anxious/angry reaction is bigger than expected, it can be helpful to consult with a clinician or therapist.
If you're curious to hear more, contact Kelsey via email or at 314-339-7640. Kelsey's office is located in Webster Groves, MO and she serves clients in St. Louis, Kirkwood, Des Peres, and surrounding areas.