Q. Power and storage consumption

So I went and read setDeepSleep and I'm thinking the following;

I need 2 things;

1. GPS coords + time periodically.
   
2. GPS Coords + time on Button press, up to 30/second very briefly.
   
   

If I log coords every 2 seconds that will let the pico sleep the most and keep a lot of tracking. Obviously up at 30 logs per second I can just cache the GPS coords and have them change as the board can send me location updates. I don't need that to exactly correlate. I assume the GPS will have a large inaccuracy anyway.

Since time was an issue I've just bought the GPS unit in the docs so the Ublox NEO6MV2[pdf]

I was assume worse case 250mA as that's is what the pico transformer says it maxes out. As you can imagine sizing a battery was getting concerting. 40mA is good to hear I know peripherals will add to that.

Can the pico sleep and leave the GPS unit logging away as it is clearly not going to wake up and get a signal in the time I'm talking about. Will I need to wire power to that directly to keep it on or best just to forget about sleeping the pico?

I'll trade you all your help for a blog post on how this goes.