LED module lifespan can vary due to frequency and environment of use. It is hard for us to predict the lifespan in months simply because everybody's usage is different.
Generally speaking we recommend changing the LED modules every six months in a production environment and as-needed in an occasional-use environment.
I would recommend purchasing a set or two of replacement lamps. They are available in our web store. Please note, our web store was quoting falsely high shipping rates for international shipment of LED modules. This has been resolved.