Here is what you should do.

Commit to an update every 4hours/2hours you decide, even if it's to say 'still broken'. 

If you deliver earlier, exceed expectations and the player base is happy, otherwise, we will still be informed.

On your communication you should state the when,why,how.

When

Server went down at XX.xx and still down.

Why

Dog ate power cable or hackers or whatever.

How

We are working around the clock to have the server up and running. Our team is running to the shop next door to get a USB cable or food for the dog.

Leaving players in the blind and to much time with no reply is the worst customer service.

These are free tips. Have fun.