I agree with the other Dan. I don't know what you're trying to say. If I had to guess... Maybe you mean "to communicate (starting) 17 minutes earlier"... Or "to communicate (in total) for 17 minutes less"...

The reason it is a number of minutes less, rather than fewer is because we consider the thing being measured to be time (uncountable) and not minutes (countable). It doesn't matter that the unit of measurement is a countable word. The thing being measured is what matters. We do this with time, money, weight ... They paid me £100 less than the others. I weigh 10 kg less than him. 'Communicate' also makes the original sentence sound odd. Should it just be 'talk'? Talk for 17 minutes less?

I'm not sure there is a simple answer to your question. It just doesn't make any sense in English.