You should also add other pre-requisites to your agreements, e.g. 7 day lead time on all work, otherwise rate is 2X standard rate if you are available at all (

You should also add other pre-requisites to your agreements, e.g. 7 day lead time on all work, otherwise rate is 2X standard rate if you are available at all (since you'd need to move existing work to make yourself available for them) Inform them of these changes in a formal way, and give them an implementation date: As of Feb 1, these are my new terms.