In general, the time I’ve spent on professional development during the summer and other breaks has been more than made up for by the energy it’s injected into my classroom every day. Spending a few hours on professional development during the summer and other breaks is more than worth it.
Spending time to learn how to do something faster and more efficiently now will almost always pay off in the long run. Every minute you save during the day in a 180 day school year adds up to 3 hours by the end of the year. If you can save 2 minutes a day, you’ve almost gotten an entire day back!