I'm currently subbing while I complete my Master's program. Speaking from experience, I have not been able to follow some lesson plans exactly because teachers have been in a rush while doing sub plans and forgot some things like worksheets, materials, or weren't specific enough on where to find something. What I can suggest is to ask your neighbor teachers next door to check in on the sub and ask if they have everything they need or if everything is clear in the plans. Also, be mindful that no matter how well-behaved your students are and structured your classroom management plan is, once a sub is in your classroom the students are going to resist routines and boundaries. Often times I have not been able to get to everything in the plans because each task and activity was like pulling teeth with students, they would take longer than usual to complete everything and it would leave little time for the next thing on the to-do list.

Having a sub fill in for a day or for a week can be a tricky one to tackle as you want to ensure the students stay engaged but also don't cause a distruption. If you know it will only be for a day, a video/movie with a follow along sheet is always a safe option.

I would create a basic plan for subs that can be easily replicated any day of the year. As much as you want them to continue the lesson, it can be very tough for them to have to explain material they haven't been involved in.